GL Gem Spectrometer

Introduction

We are proud to offer this economically priced and efficient portable spectrometer (UV-VIS-NIR, 300 – 1,000 nm) which can be operated from the USB port of a laptop computer. No additional drivers are necessary; the easy to learn GLGemSpec software displays both absorbance and transmittance spectra.

The GL Gem SpectrometerTM is an innovative and advanced gem testing instrument for experienced gemmologists, gem merchants, mineral collectors and others; it is also an excellent educational tool. It replaces the traditional hand-held spectroscope and avoids potential eye damage if the latter is used with a strong halogen light. The unique gem holder with halogen light source is mounted directly onto the spectrometer allowing fast real-time spectral analysis and bulk testing of both rough and faceted gemstones.

There are GLGemSpec users around the world including: Australia, Brazil, Canada, Czech Republic, Germany, France, Greece, Hong Kong, Indonesia, Malaysia, New Zealand, Philippines, South Africa, Sri Lanka, Switzerland, Sweden, UK and USA.

I utilize my GLGemSpec to assist me in identifying and verifying gemstones from suppliers. The accuracy is better than the human eye in observing the spectral data. When there is something that doesn’t appear as expected during testing I scrutinize the data more closely. Having the advantage of covering a large spectrum the GLGemSpec allows me to process more data about the products prior to sale or resale and assists in keeping records of those items.

- R. Kreinbrink, Owner, SOC Jewelry

Information Material

Specifications

Specifications of the GL Gem Spectrometer™

  • Weight: 510 grams
  • Dimensions: 170 mm x 100 mm x 50 mm
  • Detector: Toshiba TCD1304AP linear array (enhanced by a proprietary process)
  • Detector range: 200 – 1100 nm
  • Pixels: 3648 Pixel size: 8 mm x200 mm
  • Signal-to-noise ratio: 300:1 A/D resolution:14 bit
  • Fiber optic connector: SMA 905 to 0.22 numerical aperture single-strand optical fiber
  • Wavelength and Optical resolution: 300-1000 nm < 1.0 nm with 25 µm slit
  • Exposure time: 2.5 ms-10 s CCD reading time: 14 ms Data transfer speed: 200 ms / 100 ms (2 points binding)
  • Power consumption: 200mA @ 5V from computer interface: USB 2.0, HID 2.0 (USB cable included)
  • Operational system: Windows XP/Vista/Windows 7 32/64 bit and others; with proprietary firmware for GL Halogen 10W Gem Holder
Package

Portable GL Gem Spectrometer System with GL Halogen 10W Gem Holder (included)

Package includes:

  • GL Halogen Gem Holder
  • GL Fiber Probe and diffuser (optional)
  • USB Cable to connect to USB port of computer
  • 12/15 Volt power supply for light holder (110 – 240 V, includes international adaptor plugs)
  • software GLGemSpec (Version 2.5) with single user license
  • CD with “How to Get Started” instructions
  • “Pragmatic Spectroscopy for Gemologists” by Hanneman
  • access to data-base with over 350 reference spectra and 100 on-line image gallery

PRICE : Can$ 1,595.00 (additional fees may be charged to foreign credit cards)

* Approximate prices in USS$ 1,595.00, Euros 1.200,00 are for direct bank transfer (currency exchange as of March 1, 2012). Please request pro forma invoice for shipping options outside North America; allow 2 – 4 weeks for delivery.

GLGemSpecPack

 

Setup for external illumination of sample with Xenon flashlight

For work with gemstones set in jewellery and larger samples we recommend the GL Fiber Probe with diffuser and/or the GL Fiber Holder which can be purchased separately.

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.

Results may vary dependent on light source and its position, sample size (affecting path length) and orientation, etc.; spectra will look different from those found in the database and/or obtained with the GL 10W Halogen Gem Holder.

Free Delivery to Canada and Continental USA

Click here to order the GL Gem Spectrometer

Click here to register in the next GL Gem Spec Workshop

Specifications of the GL Halogen Gem Holder

GL Halogen 10W Gem Holder with built-in cosine corrector, 20 x 20 mm opening, SMA 905 coupler, cooling fan. Similar to an integration sphere the built-in halogen light source is internally diffused by the holder’s black matte finish.

This unit is included in the basic GL Gem SpectrometerTM package.

  • Weight: 80 gr
  • Dimensions: 75 x 50 x 27 mm
  • Size of opening: 20 x 20 mm
  • 12 – 15 V/1.5 A power adapter (110 – 240 Volts, international adapter plugs)

This light holder has been optimized for the VIS-NIR 400 – 950 nm range; with the additional diffuser adapter other light sources such as UV LED, Xenon flashlights, etc. can be used. It has a SMA 905 coupler and can be mounted onto spectrometers of other manufacturers; please contact us to confirm compatibility.

Price: Can$ 295.00 (SPECIAL ORDER)

Requirements

System Requirements

Portable GL Gem Spectrometer

The GL Gem Spectrometer™ requires a computer with a USB port (no separate drivers necessary, USB 2.0/HID 1.0 compliant). The software package contains the GLGemSpec program (Windows XP/Vista/Win 7 for 32/64 bit and LINUX/Mac OSX tested with wine 0.9.20 and MacOS inside VirtualBox); also provided is a runtime package for LabVIEW 7.1 (for developers the VIs for LabVIEW version 7.1 and 2009 are provided). A single user license is provided for each GL Gem Spectrometer system.

The recently updated GLGemSpec program has a spectral colour bar for reference and a zoom feature with a fixed 400 – 700 nm range and user defined range. Version 2.5 has a normalization feature built-in to allow for better comparison of user spectra; the software works only with the modified firmware of the GL Gem Spectrometer

The GL Halogen 10W Gem Holder is an exclusive design of Gemlab Research & Technology and is protected by copyright laws. Users of the GLGemSpec system have access to the Gemlab R & T spectra database which is available on-line

Our Warranty and Commitment

The GL Gem Spectrometer is an advanced gem testing instrument for users who have a good understanding of spectroscopy and should be familiar with the use of a traditional gemmological spectroscope and the interpretation of spectra. The instrument is not capable of identifying or naming a sample; it should be used with other gem testing tools before arriving at a conclusion. If you are not satisfied with the performance of the spectrometer we will accept returns within 10 days but have to charge a restocking fee of 10% to cover our expenses of shipping/handling and recalibration if necessary. The purchaser is also responsible for the shipping and insurance to return the item.

We will repair and replace your GL Gem Spectrometer if necessary due to defective parts, etc during the first 6 months unless other consumer protection regulations exist in your country. We also offer free firmware/CCD upgrades within 12 months if shipped to us at your cost and risk and we will return the unit to you at no cost. After 12 months a processing fee of $ 295 will be charged which covers the firmware update with any CCD upgrade (can be customized), re-alignment and recalibration, etc. and return shipping charges; other repair services upon request. Software updates are always free.

Spectra

Transmission Spectra (non-polarized) obtained with the GLGemSpec

GLGemSpecTransm GLGemSpec GLGemSpec
Synth. flame fusion ruby Unheated blGR Pailin sapphire Pink cubic zirconia

Note: Transmission dips correspond to dark lines or bands seen in a hand-held spectroscope

Converted and Normalized Absorption Spectra

 

GLGemSpecAbs GLGemSpec GLGemSpec
Synth. flame fusion ruby Unheated blGR Pailin sapphire Pink cubic zirconia

Download the archived GLGemSpec files “RubySynFlame.fak and Reference.fak” (.rar file), and import for smoothing, normalization, base-line correction, zoom, editing into Spekwin32 - free optical spectroscopy software revised Version 1.71.6 by F. Menges.

Corrected transmittance spectrum of synth. flame fusion ruby

The non-polarized spectrum of flame fusion ruby in the graph below shows corresponding absorption lines and bands as would be seen in a diffraction grating hand-spectroscope.

Corrected transmittance spectrum (non-polarized) of synth. flame fusion ruby as seen in the GLGemSpec interface:

For example if transmission for certain wavelengths (in nm) is LOW absorbance for those wavelengths will be HIGH (in a conventional spectroscope one would see dark lines or bands at these positions; indicated as bars and lines).

Noise visible below 410 nm is due to limitations of the halogen light bulb. We could improve readability in the 400 nm and below as well as above 900 nm by using a higher voltage for the halogen bulb.

For experiments LW and SW UV LEDs can be used to illuminate samples in the light holder. A multi-bandpass detector coating might be required to eliminate second-order effects. See below.

Typical absorption in the 920 – 940 nm range of copper bearing tourmaline (edited in Spekwin32) Jadeite, Burma – naturally coloured with typical absorption lines at 437 nm, 630 nm, 655 nm and 690 nm (edited in Spekwin32)
Typical 415.5 and 478 nm peaks for Cape type Ia diamond Irradiated diamonds with typical GR-1 band at 743 nm

Emission spectrum of UV LED 365 nm (Nichia, black), LED 395 nm (blue), IR LED 835 nm (red) – Synth.flame fusion ruby, scope mode with emission peaks, excitation source UV LED 395 nm (edited in Spekwin32).

Second-order effects from diffraction at 750 and 800 nm; a multi-bandpass detector coating recommended for UV light sources.

 

About

About This Project

The GL Gem Spectrometer™ system has been under development for several years. My interest in spectroscopy goes back to Bill Hannemann’s book “Video-Spectroscopy: 21st Century Gemology” published in 1988. With 2 years of university physics in my academic background I was intrigued by Bill’s concept and saw its potential but Video Spectroscopy never took off the ground.

Almost 20 years later I started using an Ocean Optics USB 2000 (200 – 850 nm) spectrometer for research in the UV range and a NIR 256-2.5 spectrometer for IR studies – but I must admit that the GL Gem Spectrometer has replaced both; it is being used every day in the Gemlab Research & Technology lab and during courses I teach at the Canadian Institute of Gemmology (C.I.G.).

The maker of the spectrometer is a post-doctoral research scientist working at a local university lab facility; he is internationally acclaimed for his work and long list of publications about transmission and Raman spectroscopy (in particular its application in stem cell research).

I would like to thank Dr. Bill Hanneman for including the GL Gem Spectrometer in his book “Pragmatic Spectroscopy for Gemologists” with many reference spectra obtained from his own collection of gems; a copy is included with the purchase of each GLGemSpec system.

The GL Gem SpectrometerTM can be used in LabVIEW environment; VIs provided for developers.

Spectrograph provided by John Harris, Gemlab.UK

Spectral Output of GL Halogen Holder and External Xenon Light Source

Uncorrected transmission spectrum in SpectraSuite (scope mode) of synth. ruby

GL Halogen 10W Gem Holder mounted onto USB4000
 

 

Vancouver, B.C. – September 1, 2010

Wolf Kuehn, B.A., M.A., Dipl.oec, F.G.A., F.G.G. – GLR&T Project Manager

© 2010 Gemlab Research & Technology, Vancouver, Canada – www.gemlab.ws

The name and logo is a registered trade mark (Registration # TMA407372 Canadian Intellectual Property Office)