GL Newsletter January 2013

Wolf Kuehn, F.G.G., F.G.A., Editor

AGTA GemFair

From the Editor

If you are visiting the Tucson gem shows please drop by at the C.I.G. booth #31 right next to Gem-A at the Galleria Level of the AGTA GemFair from February 5 – 10.

Have a look at the new GL Gem Raman TEC 532PL; the GL Gem Spectrometer will be on display as well. You can read more about new developments in this newsletter.

There will be a special Tucson price for the GL Gem Spectrometer; please go to the on-line store to see more details.

GL Gem Raman Developments

After intensive testing we have finalized the GL Gem Raman PL532 TEC and will introduce this new unit during the Tucson AGTA GemFair.

We modified the Raman spectrometer to increase the range from approx. 75 to 5,400 cm-1 at better than 10 cm-1 FWHM. There is always a trade-off affecting resolution but we were able to stay within the margins required for matching the Raman references in the RRUFF database.

We also expanded the software to allow for photoluminescence studies which may play an important role in identifying possible treatments of diamonds and gems in the future.

Another improvement for the GL Gem Raman was the addition of a thermoelectric cooling (TEC) element. The CCD (3648 pixel CCD Toshiba TCD1304AP linear array) can now be cooled down by – 35 degrees Celsius resulting in up to 150 times lower dark current.

For a gemmological lab doing appraisal work this option is not absolutely necessary as most cut and polished gemstones are fairly good Raman scatterers. However, I encountered several mineral samples which had extremely weak Raman signals and after switching on the TEC (it takes 2 minutes to reduce temperature by -30 C and another 8 minutes to stabilize at – 35 C) I was able to identify the sample. The spectral graphs look much “cleaner” and professional which is important for publication.

The TEC option is recommended for research and can be turned on when required. For up-to-date information go to our special page for the GL Gem Raman.

Nephrite

Extended range of the GL Gem Raman

For gems and minerals the typical Raman fingerprint range is from 145 – 1,500 cm-1 (as in the RRUFF database). The GL Gem Raman PL532 has now an extended range to detect Raman signals up to the 5,400 cm-1 limit (click on image to see more details).

The GLGemRaman program has the option to save both ranges as a [name].rruff file which can be directly loaded into the provided search program.

The Raman spectrum for nephrite above shows features (water band) in the above 1,500 cm-1 range which could not be seen in the previous version of the GL Gem Raman.

The RRUFF project provides for a “broad scan” database with over 1,100 references. However, due to significant increase in search time we recommend to use this database separately from the regular one.

The newest edition of Spekwin32 (revised version 1.71.6.1 from Nov 05 2012, file size: 1.3 MB by F. Menges) will import .rruff files and .fak files from the GL Gem Spectrometer.

Alexandrite Synth PL

PL option for the GL Gem Raman

The GL Gem Raman has a high quality regulated 532nm laser as an excitation source and a proper calibration system to allow scientific research. For PL studies the output of the laser has to be reduced to 50 – 100 mW.

Synthetic and natural alexandrite show the same PL peaks (click on image to see more details).

PL Option: 530 – 750 nm (broad scan) is included for experimental studies (please note that this IS NOT a fluorescence spectrometer).

With the extended range of the GL Gem Raman the PL option is already included. Users can switch the software from a [cm-1] to a [nm] scale which is commonly used for photoluminescence studies. A simple calibration procedure allows for consistent measurements.

Very limited scientific research has been done in this area. This will change in the future as we and others have started conducting studies on diamonds and selected gem materials. However, the GL Gem Raman was designed for Raman and not as a fluorescence spectrometer. We are also working on a laser PL attachment for the GL Gem Spectrometer.

An excellent overview in the interpretation of Raman and PL spectra is given in Jasinevicius, R. (2009) Characterization of vibrational and electronic features in the Raman spectra of gemstones (PDF) (MS thesis, unpublished).

Initial Photoluminescence Studies with the GL Gem Raman

The claim that photoluminescence can be diagnostic for the identification of a gemstone has to be taken with caution – in particular for the detection of HPHT treated diamonds and gemstones. With the PL option now available for the GL Gem Raman I looked at several studies to repeat and verify their testing and results. I have also tested synthetic diamonds of early Russian production in the C.I.G. gem collection.

Some of the results have already been documented in our poster “Raman Spectroscopy – A Powerful Tool in Gem Identification” (PDF, 948 KB). For further information download the GIT 2012 E-Proceedings PDF document from here (over 500 pages, .zip file, 90 MB).

PL reaction of spinel

PL studies to separate synthetic flux grown spinel from natural red spinel

The graph shows (click on image to see more details) the PL main peak for natural red spinel slightly shifted to the left.

The SSEF (Swiss Gemmological Institute) obtained a similar PL reaction using their UV-VIS-NIR spectrometer and a 312 nm LED excitation source as shown in their “Spinel: A Gemstone on the Rise” presentation (PDF)”.

Also read  “Element Analytical and UV-Vis-NIR Study of Natural Untreated Vietnamese and Synthetic Spinels” presented by Tobias Haeger during GIT 2012 (see E-Proceedings, pages 179ff).

Emerald Comparison

PL studies for emerald characterization

Comparing a synthetic flux grown emerald with a natural Colombian emerald one can see a definite shift in the luminescence peaks for chromium (click on image to see more details).

For further information read Le Thi Thu Huong’s thesis “Microscopic, chemical and spectroscopic investigations on emeralds of various origins” (pages 68ff, PDF, 2.2MB).

Origin studies for emeralds have been done based on inclusion characteristics; as a matter of fact the gemmological microscope is still the most important tool to separate natural from man made gemstones. However, with access to advanced instrumentation other approaches will become a possible.

PL Diamond

First PL studies on synthetic diamonds

The unusual PL centre (click on image to see more details) most probably originates not from a point defect in diamond, but from crystalline Al2O3:Cr3+ (ruby) inclusions or impurities in the diamond.

See “Luminescence study of defects in synthetic as-grown and HPHT diamonds compared to natural diamonds” (abstract, last sentence).

GL Gem Spectrometer Developments

The Gl Gem Spectrometer has a user base of over 100 people around the world. Already during the last Tucson gem show several visitors at our booth came up with some new ideas.

P1040540

GL Gem Spectrometer for chromaticity studies

With a firmware modification and extra software module the GL Gem Spectrometer can be used as a colourimeter displaying XYZ colour space coordinates.

For exact measurements an integrating sphere is recommended which mounts right on top of the spectrometer unit.

We are also working on a GLGemSpec laser attachment which would allow PL studies with the GL Gem Spectrometer as a low cost alternative to the GL Gem Raman PL532 unit.

Tucson Specials from the Gemlab Online Store

During January 2013 we will offer the GL Gem Spectrometer to attendants at the Tucson Gem Shows at a reduced price of $ 1,295.00 with free delivery if picked up at our booth # 31 in the Tucson Convention Centre (during the AGTA GemFair from February 5 – 10). More details here.

The GL Xenon Flashlight

This portable Xenon flash-light is ideal for use with the GL Gem Spectrometer as an external light source. Users have experimented with various setups to illuminate samples bigger than can be accomodated in the GL Gem Halogen Holder ; using a fiber probe with the GL Gem Spectrometer requires a customized setup with external lighting and will change several parameters for obtaining a spectrum.

With the Xenon flashlight I was able to clearly resolve the 415 nm line of a Cape series type Ia diamond and produce the typical 437 nm line in green jadeite.

Comparison of emission curves for halogen and xenon light source

GL Gem Spectrometer with the halogen light holder removed

Jadeite, Burma – naturally coloured with typical absorption (edited in Spekwin32)

Read Identification of dyed jadeite (PDF) from The Journal of Gemmology, 2009, 31(5-8). You can buy the GL Xenon Flashlight in our on-line store.

A Mini Microscope for Inclusion Studies

I am a collector of all kinds of gyzmos – amongst them loupes, magnifiers, USB microscopes and lately these small mini-microscopes. I tried quite a few of them and they are becoming better and better.

The best one so far costs less than US$ 5 (please e-mail me for store weblink) and has switchable LED/UV illumination.

Which one is the best?

Which one is the best?

There is a LED/UV switch

There is a LED/UV switch

Inclusions in garnet

Inclusions in garnet

Handbook of Gemmology

The Canadian Institute of Gemmology and Gemlab Research & Technology is a sapphire sponsor of the soon to be published Handbook of Gemmology. Containing over 675 colour photographs, illustrations and diagrams from 130 different contributors in thirty-six countries, ‘The Handbook of Gemmology’ is truly a global project and will be available as an eBook publication through the Gemlab Books & Instruments on-line store  in late February 2013.

GEM 250 GEM IDENTIFICATION II (Advanced Upgrade Course)

Gemmologist

- Course GEM 250-1: Sat – Wed, May 18 – 22, 10 a.m. – 4:30 p.m. (5 days, Richmond, B.C.)

- Fee: $ 995 ($ 200 exam fee for A.G. diploma not included); comprehensive study guide, Gemstone Inclusion Library, use of lab equipment and study stones.

In this course students will learn state-of-the-art techniques including immersionscope, konoscope, gemstone magnetism, IR-VIS-NIR and Raman spectroscopy, etc. designed to identify confidently any gemstone encountered in the industry. Between 100 and 120 challenging gems including the most recent synthetics are available for testing.

Here a brief list of man-made gems in our study collection: Chatham, Kashan, Ramaura, Knischka, Lechleitner, Regency, Biron, Lenix, Gilson, Tairus rubies, sapphires, emeralds, alexandrite, opal, moissanite, CVD and synthetic diamonds and many others. Gem enhancement techniques such as heat-alteration, surface colour diffusion, irradiation, HPHT and glass filling are studied.

Hands-on exercises with our in-house developed GL Gem Spectrometer and GL Gem Raman TEC PL532 system.

Prerequisite: “Gemmologist (C.I.G.)” certificate or similar gemmological qualification. Practicing gemmologists may use this lab class to up-grade their skills. It is also part of the C.I.G. Professional Development Program (AG-PDP).

To Register, please call: 604-530-8569

GEM 370 GL Gem Raman Workshop

This course is for current or future users of the GL Gem Raman system.

ramandesk - Using PowerPoint presentations the development and use of Raman spectrometers is introduced.- Learning step-by-step testing method with GLGemRaman software and searchable database

- Practical testing of a number of interesting gem materials by the participants under supervision of the workshop facilitator.

Presenter: Wolf Kuehn, B.A., M.A., Dipl.oec, FGA, FGG

  • GEM 370-1 Tue, May 21 from 6:30 – 9 p.m. (2 1/2 hours)

Location: Vancouver Airport Hotel TBA, Richmond B.C., Canada

Fee: $ 295 (limited to 5 participants). To register on-line go here.

We reserve the right to cancel courses if there is insufficient enrolment; upon return of all course materials students will receive a full refund for the tuition paid but no other compensation can be offered.

Please wait with travel arrangements until final confirmation.

View/Download and read carefully our refund policy (PDF). View/Download Application Form (PDF) or call: 604-530-8569

Discovering Gems and Jewellery

UBC Continuing Studies at Robson Square is offering as part of their CULTURAL ENRICHMENT program:

ubc – An Introduction (offered in the fall 2013)- For Connoisseurs (offered in the spring 2013)

To register contact UBC Continuing Studies.

WD511W13A Sat, March 2 – April 13, 2013, 12:30-2:30pm; UBC Robson Square. $360+tax

WD510 W13 A Sat, March 2 – April 13, 2013, 3:00 – 5:00pm; UBC Robson Square. $380+tax (Interpreted in Mandarin)

CIGem News Winter 2013

CIGem News Winter 2013 – ISSN 0846-3611 GEMMOLOGY CANADA

From the Editor:

Bagan

From Bagan, Myanmar

I wish everyone a Happy and Rewarding New Year 2013.

Myanmar was on my travel list for many years. I finally managed to organize a trip to this fascinating country on my own. During GIT 2012 I was able to meet many old and new friends; see GL Newsletter Special GIT 2012 edition.

Afterwards we went on a fabulous Post Conference Excursion to Chanthaburi and Pailin, Cambodia. An on-line slide show about my travels will be available soon.

And last but not least the annual Tucson 2013 shows are approaching. I am looking forward to meeting you personally very soon.

Wolf Kuehn, F.G.A., F.G.G.

Tucson February 2013

AGTA GemFair

If you are visiting the Tucson gem shows please drop by at the C.I.G. booth #31 right next to Gem-A at the Galleria Level of the AGTA GemFair from February 5 – 10.

We will have the new GL Gem Raman TEC PL532 and the GL Gem Spectrometer on display and the latest information about our photoluminescence studies.

As part of the World Gem Society (WGS) Tour of Tucson 2013 activities I will be giving a slide presentation “Myanmar, Thailand, Cambodia Gem Travel 2012 – with visit to the jade market in Mandalay, news from GIT 2012 Bangkok and Chanthaburi, sapphire mining in Pailin” on Friday, February 8, 2013 (time and location TBA). Please join us for an evening of fun.

A Fascinating trip to Myanmar

Travelling to Myanmar has not been easy. There are no ATMs, no credit cards or reservations for flights to be made from outside the country. All has to be done upon arrival unless you take a package tour which can be quite expensive. I was able to do my travel preparations on my own after checking with the Lonely Planet Thorn Tree forum for Myanmar for several months. Or read this Myanmar Blog.

Most tourists need a visum which may take one month to process as there is a dramatic increase in the number of tourists. For the coming months many hotels are full and flights sometimes overbooked, changed and/or cancelled. Roads are quickly being upgraded but train and bus travel is still very slow. I saw areas without electricity and in great need of better infrastructure. But it is changing quickly.

You have to bring cash to pay for goods and services. Don’t expect to change any rumpled, torn US dollar bills. Moneychangers accept only crisp, clean (and mostly uncreased) bills, and tend to only take the ‘new’ US dollar bills (with the larger full-frame heads). I have heard that $100 bills starting with the serial number ‘CB’ have been turned down. Read Monetary Mayhem From Myanmar.

But all went smoothly and for me it was one of my most exciting trips to Asia. Below some images which will provide a first impression.

Yangon is a former capital of Burma and the capital of Yangon Region. Although the military government has officially relocated the capital to Naypyidaw since March 2006, Yangon, with a population of over four million, continues to be the country’s largest city and the most important commercial centre.

Although Yangon’s infrastructure is undeveloped compared to those of other major cities in Southeast Asia, it has the largest number of colonial buildings in the region today. While many high-rise residential and commercial buildings have been constructed or renovated throughout downtown and Greater Yangon in the past two decades, most satellite towns that ring the city continue to be deeply impoverished (source Wikipedia).

Shwedagon Pagoda

Shwedagon Pagoda, Yangon

Bogyoke (Scott) Market

Bogyoke (Scott) Market, Yangon

"Mogok" ruby filled Glas

“Mogok” ruby filled Glas

Kuthodaw Pagoda, Mandalay

Kuthodaw Pagoda, Mandalay

Mandaly Hill

Mandalay Hill

From Mandalay Hill at sunset

From Mandalay Hill at sunset

Mandalay, the capital of Upper Burma, is located 600 km north of Yangon, on the banks of the Ayeyarwady River. As the second largest city in Myanmar, Mandalay has slightly over 800,000 inhabitants.

It is the capital of Upper Burma that was immortalized in Rudyard Kipling’s The Road to Mandalay, the 1887 poem that refers to the Ayeyarwady. In a country where the cities are a thousand years old or more, Mandalay is surprisingly young in comparison – “just” over 150 years old (source Wikipedia).

Jade Markets in Mandalay, Myanmar

Mandalay Jade Market

Mandalay Jade Market

Polishing jadeite

Polishing jadeite

Selection of jadeite

Selection of jadeite

A visit to the jade market in Mandalay is a must for anyone interested in gemstones. Covering several acres on a site between 38th and 39th streets west of the city centre the bustling market features countless rows of small stores, each about two metres wide, laid out in a grid. Managed by the Mandalay City Devlopment Committee, it provides an insight into the working of the larger jade industry, which is developing into an increasingly lucrative foreign income earner.

Nobody was there to collect the $ 1 entrance fee for foreigners as I was perhaps the only Western tourist surrounded by hundreds (if not thousands) of local traders in the incredible heat and noise that is hard to capture by camera.

Exploring Bagan Temples

Bagan (formerly Pagan), is one of the most famous ancient city in Myanmar. It is the place in Myanmar to admire ancient ruins. Bagan ranks alongside Angkor and Luang Prabang as one of the most amazing sights in Southeast Asia.

If you’re into ancient ruins, there’s more in Bagan than you could ever bargain for. Bagan is located on a dusty plain 300 km from Yangon.

Bagan temples

Bagan temples

Ananda Temple

Ananda Temple

View from Shwesandaw Pagoda

View from Shwesandaw Pagoda

GIT 2012 Post Conference Tour to Chanthaburi and Pailin

Chanthaburi is a province of Thailand. It is located in the east of Thailand, at the border to Battambang and Pailin of Cambodia and the shore to the Gulf of Thailand. Together with the neighboring province Trat, Chanthaburi is the center of gemstone mining, especially rubies and sapphires.

Tropical fruits are also among the main products of the province. In 2000, it produced nearly 380,000 tonnes of durian, which was 45.57% of Thailand’s durian production and approximately 27% of the world production of this fruit (source Wikipedia).

Sapphire mine

Operating sapphire mine near Chanthaburi

Bangkaja Sapphire Rough

Sapphire

Sapphire Jewellery

Pailin temple

Wat Phnom Yat, Pailin

Pailin mine

Sapphire mine in Pailin, Cambodia

Pailin sapphires

Pailin sapphires

Pailin is a small municipality in the West of Cambodia very close to the border of Thailand. The provincial capital is called Pailin City and is known to much of the world as being the area where many of the Khmer Rouge leaders came from and retreated after their fall.

In the late 1970s, Pailin was a prosperous town stemming from the extensive gem deposits in the surrounding countryside. Because of its resources, it was one of the first cities invaded by the Khmer Rouge when they began their major offensive against the national government. The city offered no resistance and the Khmer Rouge soldiers were greeted as liberators as they marched into town. In recent years a new wave of tourism began depending on its ancient temples, natural forests, animals and especially the precious stones (source Wikipedia).

GL Gem Raman PL532 TEC Spectrometer

We have finalized the GL Gem Raman PL532 TEC with a range from approx. 75 – 5,400 cm-1 at better than 10 cm-1 FWHM. Raman range (RRUFF) is from 145 – 1,500 cm-1 and broad scan range for PL studies up to 5,430 cm-1 (530 – 750 nm). TE cooled 3648 pixel Toshiba TCD1304AP linear array.

All new units have the PL option installed; other configurations available upon request. Please contact us for more information.

The Raman spectrum for nephrite on the left (click on image to enlarge) shows interesting Raman features in the region of 200 cm-1 and below and in the PL region 3,000 cm-1 and above.

Tucson Specials from the Gemlab Online Store

During January 2013 we will offer the GL Gem Spectrometer to attendants at the Tucson Gem Shows at a reduced price of $ 1,295.00 with free delivery if picked up at our booth # 31 in the Tucson Convention Centre (during the AGTA GemFair from February 5 – 10). More details here.

We also will introduce and demonstrate the new GL Gem Raman PL532 TEC.

Discovering Gems and Jewellery

UBC Continuing Studies at Robson Square is offering as part of their CULTURAL ENRICHMENT program:

– An Introduction (offered in the fall 2013)

- For Connoisseurs (offered in the spring 2013)

Gemstones have intrigued us throughout history and are reputed as symbols of wealth, power, healing and love. In this course, students explore the unique properties of gemstones that affect their value and study the locations where they are found. Participants will board a virtual tour of splendid gem collections found in museums around the world and discover the challenges in differentiating between natural and man-made gem materials. In addition, advice will be given for purchasing jewellery at various venues such as at auction.

Instructor: J. Wolf Kuehn, B.A., M.A., Dipl.oec., F.G.A., F.G.G.

WD511W13A Sat, March 2 – April 13, 2013, 12:30-2:30pm; UBC Robson Square. $360+tax

 WD510 W13 A Sat, March 2 – April 13, 2013, 3:00 – 5:00pm; UBC Robson Square. $380+tax (Interpreted in Mandarin)

To register contact UBC Continuing Studies.

C.I.G. Professional Development Program (AG-PDP)

The Canadian Institute of Gemmology is offering a self-guided study program leading to the Accredited Gemmologist (C.I.G.)® diploma for students who have completed a gemmology program with another institution.

Upon successful completion of the AG-PDP credits and fulfillment of other requirements (such as submission of a scientific paper and payment of an annual license fee) graduates are entitled to use the international recognized designation Accredited Gemmologist (C.I.G.)®.

Entrance Requirements

“Fine Jewellery Expert (C.I.G.)”, F.G.A. or equivalent from other institutions; foreign candidates may apply but must enter Canada under a visitor’s visa (no student visas available). If credentials were obtained before 2002 a practical entrance test must be passed.

Course Credits Required

  • All C.I.G. GEM 200-level courses
    • GEM 210 Diamond Grading
    • GEM 220 Advanced Gemmology
    • GEM 230 Gem Colour Grading
    • GEM 250 Gem Identification II
  • For this course it is recommended that students have basic gem testing equipment at their disposal to complete individual projects at home or at their work place; students will also learn the use of UV- VIS – NIR spectrometers. There will be a five-day practical workshop to complete the AG-PDP program.

To obtain certification as an Accredited Gemmologist (C.I.G.)® a scientific paper has to be submitted within 6 months of completion of the A.G. (C.I.G.) diploma exam. See course outline or View/Download brochure (PDF) and View/Download Application Form (PDF). If you have any further questions about the AG-PDP program please call (604) 530-8569.

Individual courses must be completed within 12 months; courses leading to a certificate or diploma must all be completed within 24 months.

For more info about the C.I.G. Professional Development Program (AG-PDP) go to Advanced (GEM 200-level) Courses or download brochure (PDF).

World Gem Society

The Canadian Institute of Gemmology is a member of the World Gem Society.

For a nominal fee you can access a variety of resources available.

GL Newsletter Special GIT 2012 edition

Follow @gemlabNEWS

Wolf Kuehn, F.G.G., F.G.A., Editor

From the Editor

I just returned from SE Asia after travelling in Myanmar, attending “The 3nd International Gem & Jewelry Conference” GIT 2012 in Bangkok and participating in the post-conference tour to Chanthaburi and Cambodia.

More about my travel and news from Thailand in the January CIGem Newsletter Winter 2013.

In this special GL Newsletter I will report briefly about interesting topics presented during the conference as I did 3 years ago for the GIT 2008 conference.

GIT 2012 The 3nd International Gem & Jewelry Conference

GIT 2012

Poster Session during GIT 2012

Held for the third time in Bangkok, Thailand and organized by the The Gem and Jewelry Institute of Thailand GIT 2012 attracted over 500 participants from around the world. It was encouraging to see many young contributors sharing their research and work projects in oral presentations and poster sessions covering a wide scope of topics from gemmology to jewellery design.

Many thanks to Ms. Wilawan Atichat, Director of GIT and her team for a superb job in organizing this event. Over half of the contributions were dedicated to the section “Gem Identification and Treatments”.

You can download the close to 500 pages of the E-Proceedings PDF document from here (zip file, 90 MB). I will refer to them in my comments and observations below; also download our poster “Raman Spectroscopy – A Powerful Tool in Gem Identification” (PDF, 948 KB).

Diffusion of Transition Metals in Gemstones

Three years ago Yong-Kil Ahn and Jong-Wan Park, Hanyang University, Seoul, Korea submitted a research poster to GIT 2008 “Comparative study of Cr3+ diffusion in proton and electron irradiated chrysoberyl” (PDF, 325 KB). It was work in progress and I maintained contact with the authors to stay up-to-date.

In the meantime they published two other articles to be shared: “Diffusion of chromium in sapphire: The effects of electron beam irradiation” (PDF, 960 KB) and “Effects of electron-beam irradiation, a thin-Ti layer, and a BeO additive on the diffusion of titanium in synthetic sapphire” (PDF, 972 KB).

As part of their research several diffusion experiments were performed and various methods for enhancing the diffusity were attempted as demonstrated in their poster “Diffusion of Transition Metals in Gemstones using various Specimen Preparation Methods” (E-Proceedings, page 164ff). Photoluminescence results for the specimens using a 325 nm He-Cd excitation source show a clear difference between the fluorescence of sapphire before and after irradiation.

Ion Beam Treatment and Analysis

Ion beam treatment – a rather expensive method at the present time due to the high cost of the equipment – can be used to not only improve the colour but also the clarity and luster of gemstones. In their “Overview of Ion Beam Treatment of Gemstones in Thailand” (E-Proceedings, page 252ff) the Thai researchers tested and treated a variety of gemstones such as rubies, sapphires, topazes, spinels and garnets from Thailand, Myanmar (Burma), and Africa.

Apatite Treatment

Korean researchers conducted further studies and showed their work in two posters:

“Spectroscopic Characteristics of Electron-beam Irradiated Apatite” (E-Proceedings, page 272ff) and

“The Color Change of Hackmanite from Myanmar by Exposure to UV Rays and Irradiation by Electron Beam” (E-Proceedings, page 276ff).

The ion beam technology has been recently applied for the first time in Thailand for gemstone analysis, particularly, the Proton Induced X-ray Emission (PIXE) which is an effective and nondestructive way to quantify trace elements analysis at ppm level.

The Thai researchers conducted an “Ion Beam Analysis of Spinel” (E-Proceedings, page 220ff) and introduced a “Novel Ion Beam Technique for Lead Detection in Rubies” (E-Proceedings, page 244ff).

The ion beam techniques give an advantage over conventional techniques in term of lead content detection. In summary they warned that “Rubies treated by paw-mai method contained remarkable high concentration of lead and they may be harmful to gem consumers” and unsafe for the treaters of these gem materials as well.

New Treated Sapphire

Since early 2012, a new type of treated blue sapphire has been encountered in the trade. During the post conference tour in Chanthaburi Dr. Pornsawat Wathanakul made samples available to the participants and a brochure was distributed as well.

I tested my sample under immersion in methylene iodide and found that it showed colour concentrations along the facet junctions reminding of the old “surface-diffused” sapphires. In addition, in their presentation “Newly Treated Blue Sapphire: a Preliminary Investigation” (E-Proceedings, page 264ff) they detected the presence of beryllium which may play a role in the colouration of this blue sapphire. A “Round up on Gemstone Hot Issues in 2012″ (E-Proceedings, page 264ff) was given by the same group of Thai researchers.

Lithium Treatments

Ted Themelis gave an oral presentation of “Lithium-Treated Gemstones” (E-Proceedings, page 228ff) with first hand knowledge of this type of treatment; it has been applied to blue sapphires, grossularites, tourmalines and other gems to improve their colour, diaphaneity and lustre since 2011.

As the outcome of the treatment in many cases is unpredictable it is difficult to know the exact mechanism involved in this treatment. It would require a complete analysis of the samples before and after treatment.

Lithium Treated A typical rough, untreated African grossularite used in the lithium process (left); after heating
with lithium-based additives, most stones turned reddish-orange (middle, 3.59 carats), rarely intense red (right, 22.71 carats).

Diamonds and Organic Gems

In this section several contributions were made about “CVD Synthetic Diamonds and their Proper Identification” (E-Proceedings, page 301ff) and “Research on CVD Gem Diamonds” (E-Proceedings, page 303ff).

My Canadian colleague Branko Deljanin spoke about “Screening and Identification of Coloured and Colourless Diamonds for the Synthetic Origin using the UV Lamp and the Polariscope mounted on a Microscope” (E-Proceedings, page 308ff).

In summary further research is necessary to properly identify all the treatment combinations applied to both natural and synthetic diamonds. Our own recently developed GL Gem Raman PL532 will become an important tool not only for the identification of coloured stones, but also to check for type IIa HPHT treated stones (IIa with HPHT annealing or without).

There were many more contributions such as from my Russian colleagues on “Identification of the Garnet Chemical Composition and Color Causes by Express Raman and Visible Spectroscopy” (E-Proceedings, page 214ff).

I selected the above contributions as they covered the most interesting subjects and issues for someone working in a gemmological laboratory like myself. Download and read the GIT 2012 E-Proceedings (PDF, 100 MB – large file).

Tucson Specials from the Gemlab Online Store

During January 2013 we will offer the GL Gem Spectrometer to attendants at the Tucson Gem Shows at a reduced price of $ 1,295.00 with free delivery if picked up at our booth # 31 in the Tucson Convention Centre (during the AGTA GemFair from February 5 – 10). More details here.

We also will introduce and demonstrate the new GL Gem Raman PL532.

Bangkok GIT 2012 Pailin, Cambodia

CIGem News Summer 2012

ISSN 0846-3611 GEMMOLOGY CANADA – Wolf Kuehn, F.G.G., F.G.A., Editor

Follow @CIGemNews

From the Editor

After a quiet summer season we are getting ready for a busy fall semester. If you live in the Vancouver area please drop by at our Info Session on August 31. I am also teaching a new course “Discovering Gems and Jewellery” as part of UBC’s (University of British Columbia) Cultural Enrichment program at Robson Square in Vancouver, B.C.; there is a section in English and in Mandarin interpreted (study materials in Chinese).

Mark your calendar for the GIT 2012 conference in Bangkok, Thailand (December 12 – 13); I will be attending and have submitted an abstract about “Raman Spectroscopy – a powerful tool in gemstone identification”. More info to follow in the next GL Newsletter September 2012.

Vancouver Info Session August 31, 2012

We have scheduled the annual info meeting for Friday, August 31 from 1:00 – 5:00 p.m in Room C-010 at UBC Robson Square, 800 Robson Street, Vancouver.

The Translink web site allows you to plan your trip via transit to UBC from any Lower Mainland location.

To access the Robson Square’s underground parking travel to the corner of Howe Street and Nelson Street (Howe Street is a one-way street). Once you have entered the parking lot follow the directional signs to UBC Robson Square parking area.

Prospective C.I.G. students can pre-register in person for local C.I.G. courses and pick-up study materials and text books if already registered. Please consult the 2012 schedule for Vancouver classes.

During the info session we will demonstrate the GL Gem Raman and the GL Gem Spectrometer; visitors are welcome to bring interesting samples – in particular jadeite pieces as we are conducting a study for proper identifcation and treatment detection. Please contact us at (604) 530-8569 for further information.

 

Discovering Gems and Jewellery – an Introduction

ubc

UBC Continuing Studies at Robson Square in Vancouver, B.C. is offering as part of their CULTURAL ENRICHMENT program:

WD508F12A Sat, Sep 22-Oct 27, 12:30-2:30pm; UBC Robson Square. $360+tax

WD508F12B Sat, Sep 22-Oct 27, 3-5pm; UBC Robson Square. $380+tax (Interpreted in Mandarin)

Gemstones have intrigued us throughout history and are reputed as symbols of wealth, power, healing and love. In this course, students explore the unique properties of gemstones that affect their value and study the locations where they are found.

Participants will board a virtual tour of splendid gem collections found in museums around the world and discover the challenges in differentiating between natural and man-made gem materials. In addition, advice will be given for purchasing jewellery at various venues such as at auction.

Instructor: J. Wolf Kuehn, B.A., M.A., Dipl.oec., F.G.A., F.G.G.

 

GL Gem Spectrometer Anniversary Sale

Join the growing number of GL Gem Spectrometer users around the world. For a limited time save $ 100 during our Second Anniversary Sale (until August 31, 2012). Click here for more information.

Click here to order the GL Gem Spectrometer

Click here to register in the next GL Gem Spec Workshop

The GL Professional Refractometer (on-line price $ 369.95) is in stock again.

Omphacite and Jadeite

In the GIA Lab Updates of the G&G eBrief (April 10,2012) “a green cabochon in a piece of jewelry was submitted to the Carlsbad laboratory in early 2012. Although standard gemological properties indicated jadeite (1.66 RI, chrome lines, and a 437 nm line in the desk-model spectroscope), its identity was questioned by a staff gemologist because the texture was slightly more granular than normal. Surprisingly, its Raman spectrum provided a very good match for omphacite, using reference spectra from the RRUFF database. The identity of each RRUFF specimen has been confirmed by X-ray diffraction analysis.”

We have tested all the “jadeite” specimen in the C.I.G. gem study collection but so far not encountered omphacite. There are 2 Raman spectra for omphacite provided in the GLGemRaman database; users should not have any difficulty in separating jadeite from omphacite. An update is available in the GLGemRaman Support section.

“GIA’s laboratory reports will now call such stones omphacite jade. In doing so, we are expanding the term jade to encompass more minerals than just jadeite and nephrite, including those stones that test gemologically as jadeite but are actually omphacite”.

GLGemRaman Software Update 1.4

All GL Gem Raman users should have received version 1.4 of the GLGemRaman software; it has an automatic calibration feature built into the software using a calibration sample. This should be done from time to time to get best matches with the RRUFF databse.

In case the unit has been exposed to severe physical/thermal shock a more comprehensive optimization procedure should be conducted by an experienced technician. We have presently support personnel in Canada, USA and Germany (for European clients).

Please contact us for more information at (604) 530-8569.

The GL Gem Raman is available now

 

I have been using the GL Gem Raman for the last 6 months checking stones in the C.I.G. gem study collection; the instrument is an enormous time saving device as it eliminates the use of all other gem testing instruments in many cases. It takes me less than one minute to identify a gemstone (even if set in a piece of jewellery) as to what it is. Of course the microscope is still absolutely necessary for final identification if the stone could be man-made. For highly fluorescent materials (Raman signals are weak and can be “overwhelmed” by fluorescence) the intensity of the laser has to manipulated to get acceptable results; or as an alternative the GL Gem Spectrometer can help.

In general all advanced gem testing instruments have advantages and disadavantages but in a busy lab situation a Raman is an extremely valuable tool and can pay for itself quickly.

GIT Conference in Bangkok

The Gem and Jewelry Institute of Thailand proudly announces the 3rd International Gem and Jewelry Conference or GIT 2012, the third of its kind after the successful predecessors’ GIT 2006 and GIT 2008.

It is another GIT’s landmark technical event to be held from December 12-13, 2012 in Bangkok, and followed by a post-conference excursion option to visit Chanthaburi, and Pailin of Cambodia during December 14-16, 2012.

GEM 250 GEM IDENTIFICATION II (Advanced)

  • Course GEM 250-2 Sat – Tue, Nov. 17 – 20, 10 a.m. – 4:30 p.m.(limited space please pre-register)
  • Location: Richmond, B.C. Airport Hotel
  • Prerequisite: “Gemmologist” certificate or similar gemmological qualification.
  • Fee: $ 995 includes comprehensive study guide, Gemstone Inclusion Library, use of lab equipment and study stones.

In this course students will learn state-of-the-art techniques including immersionscope, konoscope, advanced spectroscopy, etc. designed to identify confidently any gemstone encountered in the industry. Between 100 and 120 challenging gems including the most recent synthetic and imitation gem materials are available for testing.

Here a brief list of man-made gems in our study collection: Chatham, Kashan, Ramaura, Knischka, Lechleitner, Regency, Biron, Lenix, Gilson, Tairus rubies, sapphires, emeralds, alexandrite, opal and many others. Gem enhancement techniques such as heat-alteration, surface colour diffusion, irradiation and glass filling are studied.

Hands-on exercises with our portable  GL Gem Spectrometer and GL Gem Raman system. Practicing gemmologists may use this lab class to up-grade their skills.

To Register, please call: 604-530-8569

GEM 370 GL Gem Raman Workshop

This course is for current or future users of the GL Gem Raman system.

  • Using PowerPoint presentations the development and use of Raman spectrometers is introduced.
  • Learning step-by-step testing method with GLGemRaman software and searchable database; procedure of proper calibration with Laser Glasses (190-548nm);
  • Practical testing of a number of interesting gem materials by the participants under supervision of the workshop facilitator.

GEM 370-3 Thu, Nov 15 from 6:30 – 9 p.m. (2 1/2 hours)

Location: Vancouver Airport Hotel TBA, Richmond B.C., Canada

Fee: $ 295 (limited to 5 participants). To register on-line go here.

We reserve the right to cancel courses if there is insufficient enrolment; upon return of all course materials students will receive a full refund for the tuition paid but no other compensation can be offered.

Please wait with travel arrangements until final confirmation.

For more info about the C.I.G. Professional Development Program (AG-PDP) go to Advanced (GEM 200-level) Courses or download brochure (PDF).

If you have a cellphone scan the QR code and you will be taken directly to the website of the Canadian Institute of Gemmolgy.

Save the bookmark!

GL Newsletter June 2012

From the Editor

I attended a very informative Geo-Raman conference in Nancy, France and learnt about the most advanced research from many young and aspiring scientists. We are looking forward to attending the XIth meeting which will be held in St. Louis, MO, USA in 2014.

We are now preparing for the GIT 2012 conference in Bangkok, Thailand (December 12 – 13) with a paper on the use of the GL Gem Raman in gemstone identification.

On a negative note – on several occasions I have been contacted by a group “of respected gemologists and dealers ….. ” with malicious and damaging allegations. In general I do not react to this type of  “anonymous crap” supposedly representing this industry.

I wish everyone a pleasant summer (or winter if you live in the wrong place!).

Brief Report from the Geo-Raman Xth Meeting

The Geo-Raman Xth Meeting was held in Nancy from June 11-13; over 50 presentations and close to 100 poster sessions were attended by more than 130 participants from around the world. The conference covered Raman spectroscopy applied to Earth Sciences and demonstrated the rapid developement of this technology in numerous applications; see program (PDF).

From 3D Raman units with imaging systems costing $100k+ to proposals of UV gated Raman spectrometers  reducing luminescense by a factor of 100 (which caught many participants by surprise). The instrument shows the typical Raman diamond feature only for type IIa; it would be a valuable instrument for CVD detection. However, the parts needed to be UV capable and a 244nm pulsed laser still costs $ 20,000.

Another interesting study about mesocrystal poymorphism in nacre demonstrated the potential of Raman spectroscopy; see preparatory studies “Nano-Composite Structure of Nacre Biocrystal” (PDF) and “Voronoi Growth Model of Sheet Nacre ” (PDF). The authors believe that AFM and Raman spectroscopy is ideally suited for studying mesocrystals and their polymorphic growth.

Raman spectroscopy can be used for provenance studies of heavy-minerals. The study has been extended to Feldspars and may expand Joel Arem´s observations on plagioclase feldspars (PDF). We will make the poster containing numerous Raman graphs of Labradorite found in the Himalaya–Tibet orogenic belt available in the next GL Newsletter.

Very interesting research is being conducted by the German Research Centre using a hydrothermal diamond-anvil cell resulting in growth of jadeite, albite, paragonite in an assemblage silicate glass and aqueous fluid heated to 600 degree Celsius.

Gemlab Research & Technology submitted an abstract and a poster “The GL Gem Raman- a powerful tool in gem and mineral identification” (950KB,PDF). The unit was demonstrated to interested parties and well received.

A selection of papers presented at the GeoRamanX Conference will be published as a thematic issue of the European Journal of Mineralogy (EJM). In the meantime several gemmology related studies were presented during the 6th International Congress on the Application of Raman Spectroscopy in Art and Archaeology (RAA 2011) in Parma, Italy; download the Abstracts (PDF) here.

Raman spectroscopy is an ideal technology for gems and mineral identification. The GL Gem Raman quickly can tell the difference between diamond, cubic zirconia, glass and zircon, distinguish jadeite from nephrite, separate real from faux pearls, tell whether it is ivory or plastic; it works great on beads, carvings and gem materials set in jewellery. For more info go to the product page.

Update for GL Gem Raman Software

Version 1.3 of the GLGemRaman software has now a base-line correction feature. Based on a similar algorithm as used in the CrystalSleuth software the raw GLGemRaman spectrum can be “forced down” making it easier to compare with reference spectra in the data-base; the corrected Raman spectrum will be saved both as a complete .fak file and can be directly imported into Spekwin32 for further editing and as a .rruff file for quick search in the RRUFF database.

GL Professional Refractometer available again soon

Our new professional refractometer sold out quickly. We will have new supply by mid-July.From GL Newsletter April 2012: Very impressive is the performance of the new and redesigned GL Professional Refractometer (on-line price $ 369.95); it comes in a white plastic casing and was actually properly calibrated.

The refractometer has a high hardness CZ (cubic zirconia) hemicylinder and a built in LED-based yellow light source that is powered by either two AA batteries or a small 110-240V power supply with 3VDC output.

Anonymous “Andesine Perpetrators” resort to cyber-bullying

Since the conclusion of the “Art Garabedian/DSN vc Robert James Andesine case ” (Court document, PDF) I have been approached several times by an anonymous group “of respected gemologists and dealers on three continents dedicated to gemological integrity and full disclosure of all treatments” with malicious allegations about our school, our products and questioning my personal integrity. I believe I know who these people are and I think it is time to distance one-self from these unprofessional members of the gemmological community. I also reserve the right to take legal steps to stop this personal bullying and libel.

As a member of the World Gem Society I agree fully with the response of Robert James (can be read here); also his article on Wikipedia & Internet Cyber Bullies (PDF).

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© 2012 Gemlab Research & Technology, Vancouver, Canada