Gem Inclusion Library

SORRY the Gem Inclusion Library is now OUT OF PRINT.


Gemlab Books and Instruments, a subsidiary of the Canadian Institute of Gemmology is the exclusive distributor of the “Gemstone Inclusion Library”; it contains 25 pages, 5.5″x8.5″, with 120 b&W line-drawings, 1 colour plate, CD-ROM disk loaded with over 100 JPEG picture files.

Cost is CAN$ 39.95


The Gemstone Inclusion Library was published over 10 years ago and since then many new gem materials- genuine, man-made and/or treated have appeared in the markets. It would be an immense task to produce an updated Gemstone Inclusion Library and we simply do not have the funds and resources to do this; as a consequence the booklet is out-of-print and copies for sale are limited. However, 90 – 95% of gemstones in the market are those illustrated in the black&white drawings of the manual. The concept demonstrated is not antiquated but rather modern and innovative for serious gem identification today: IMMERSION.

Many gemmologists have never learned how to use this method effectively because it is messy and to work with a “dry” microscope is easier and much faster. But recent gem enhancements such as surface diffusion, bulk diffusion, beryllium treatments, etc can only be detected with the stone immersed. Amateurs use water and baby oil in an immersion dish; professionals use a liquid which is close to the refractive index of the stone to be tested. These organic liquids such as methylene iodide (the same liquid used in contact fluid for the refractometer), bromoform, benzyl benzoate and others may be available in your local drug store or from special suppliers. Afterwards the stones have to be cleaned thoroughly in neothene or alcohol because all organic liquids attack plastics and other surfaces.

Please go to The Appraisal Corner where you will find links to other websites with interesting inclusion images. For an inclusion glossary go here.

Gemstone Inclusion Library v1.8


If you have purchased version 1.0 or higher of the Gemstone Inclusion Library you can now upgrade to version 1.8 below. Please note: The update only works with your purchased Gemstone Inclusion Library; it does not contain any images.

Gemstone Inclusion Library, Version 1.8 Update (Feb. 1, 2002) (, 34 kB)

Over 120 Black & White line drawings are used in the Gemstone Inclusion Library manual to illustrate typical inclusions in synthetic and natural gemstones.The enclosed CD contains 100 colour images of inclusions obtained from an immersionscope which can be viewed in a web-browser or printed out.

J. Wolf Kuehn, C.I.G. Director of Education, has compiled numerous inclusion pictures from the comprehensive study collection of the Canadian Institute of Gemmology. It is an ideal reference for serious gemstone identification. The guide contains 120 detailed line-drawings of typical inclusion features found in synthetic and natural gemstones; a diskette with over 100 colour micro-photos of inclusions (in JPEG and .htm format) is included. Most of the pictures were taken with an immersionscope (horizontal micsrosope) allowing the study of internal features with more ease and clarity. If a colour-printer is available high photographic quality can be obtained with special paper.

From the Author’s Introduction

After many years of teaching C.I.G.’s Gem Identification courses I felt that other students, practising gemmologists and appraisers might equally benefit from the various instructional materials used in the “Accredited Gemmologist” diploma program such as the Gemstone Inclusion Library.

When attending conferences, workshops and gem shows it was one of my most important tasks to look for new gem materials – natural, synthetic, invented, enhanced and/or assembled. Today I can state with great confidence that almost any possible gemstone encountered in the market-place is represented in the study collection of the Canadian Institute of Gemmology (C.I.G.); that includes natural gems such as Taaffeite and Benitoite as well as synthetic gems such as Knischka and Lechleitner rubies and emeralds.

During an evaluation of a gem or a piece of jewellery the most important part is the proper identification of the gem materials. In most cases this is a straightforward procedure; however, if the gem happens to be a ruby, sapphire, emerald, alexandrite or opal, it may require the microscope to study the internal features before deciding whether it is a natural or man-made product.

This is particularly true in the case of the latest flux-fusion and hydrothermal synthetic gems which include the Kashan, Knischka and Ramaura rubies, the Chatham, the Lennix, Biron and Regency emeralds and others. Most of us do not have access to more sophisticated testing equipment such as the electron microprobe or a Raman spectroscope. Our work must depend on the recognition of visual clues including diagnostic inclusions, colour zoning and growth patterns.

I wish to thank the Gemstone Training Centre Ruppenthal in Idar-Oberstein, Germany for their support in this project.

J.Wolf Kuehn, Director of Education, C.I.G.
Vancouver, B.C., August 1996

Die Welt der Edelsteine und Juwelen

Below are a few images obtained from a CD-ROM “Die Welt der Edelsteine und Juwelen” published by Koch Media GmbH-Austria, 1995 (the images are posted for educational purposes only)

m3 m1 m4
Liquid inclusion “trapped” in a topaz Crystal features under polarised light Heated air-bubbles moving in liquid inclusion

Animation 1: Air-bubbles moving around in crystal

Animation 2: Beautiful inclusion picture of topaz The bubbles are probably fluid carbon dioxide; see Inclusion Glossary below.

Inclusion Glossary

Inclusion Reference Library