Gemology Books Bibliography

First Published: 28 September 2026

Gemology Books Bibliography

Explore books on gems, gemology, jewelry and mineralogy in Four Treasures, the Lotus Gemology reference database. This bibliography brings together matching book records from the collection, with publication details, abstracts and cover images where available.

Gemology Book References

The list below matches books concerning gemology and related subjects in the database's searchable fields. Some works cover several branches of gems, jewelry or mineralogy.

41–60 of 3,434 matching references

Madagascar sapphire: Crystal blue persuasion

Hughes, E.B. and Hughes, R.W. (2018)

Journal Article · Source: Rivista Italiana di Gemmologia – Italian Gemological Review · Issue: No. 4 · Pages: pp. 44–54

Abstract

A look at sapphire in southern Madagascar, including a description of its inclusions.

Keywords

gems, corundum, Madagascar.12, inclusions

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Understanding inclusions: Superficial sapphires

Hughes, E.B. (2018)

Journal Article · Source: Gems&Jewellery · Volume: Vol. 27 · Issue: No. 2, Summer · Pages: p. 31

Abstract

In the second of a four-part series for Gems&Jewellery, Bangkok-based gem testing lab, Lotus Gemology, shares insightful pairs of photographs that, when placed side-by-side, reveal the full story of an inclusion or treatment. In this issue, we explore heat-treated sapphires...

Keywords

gems, corundum, inclusions.5, color.4

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Understanding inclusions: Discovering crystal types

Hughes, E.B. (2018)

Journal Article · Source: Gems&Jewellery · Volume: Vol. 27 · Issue: No. 1, Spring · Pages: p. 40.

Abstract

In a new series for Gems&Jewellery magazine, Bangkok-based gem testing lab Lotus Gemology delves into its photomicrograph archive, Hyperion, to help gemmologists tackle tricky inclusions. In this inaugural column, we discover the difference between crystal types in ruby and sapphire.

Keywords

gems, corundum, inclusions.5

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Understanding inclusions: Regarding rutile

Hughes, E.B. (2018)

Journal Article · Source: Gems&Jewellery · Volume: Vol. 27 · Issue: No. 4, Winter · Pages: p. 40

Abstract

In the final part of a year-long series for Gems&Jewellery, Billie Hughes of Bangkok-based gem testing lab, Lotus Gemology, shares pairs of photographs that, when placed side-by-side, reveal the full story of an inclusion or treatment. In this issue, we delve deeper into rutile inclusions in ruby and sapphire...

Keywords

gems, corundum, inclusions.5, rutile silk, primary rutile

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Understanding inclusions: Unmistakable mines

Hughes, E.B. (2018)

Journal Article · Source: Gems&Jewellery · Volume: Vol. 27 · Issue: No. 3, Autumn · Pages: p. 40

Abstract

In the third of a four part series for Gems&Jewellery, Bangkok-based gem testing lab, Lotus Gemology, shares pairs of photographs that, when placed side-by-side, reveal the full story of an inclusion or treatment. In this issue, we explore how inclusions can help to reveal the origin of rubies...

Keywords

gems, corundum, inclusions.5, Burma.12

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G&G Micro-World: Star spinel with four and six rays

Hughes, E.B. (2018)

Journal Article · Source: Gems & Gemology · Volume: Vol. 54 · Issue: No. 2, Summer · Pages: p. 230

Abstract

Lotus Gemology receives submissions of star stones on a regular basis, so when we first saw the specimen shown here, it appeared to be one among many of our usual stones to test. Upon closer examination, however, we realized it was not a star sapphire, but something much more rarely seen: star spinel. At first glance, the the cabochon’s dome displays one six-rayed star (figure 16), similar to what we see in star corundum. But if we follow each ray to the sides of the stone, we can also see a four-rayed star (figure 17). These stars are created from numerous dense, short needle-like particles. Once we examined a small polished area on the cabochon’s base, we found that there are actually two distinct types of exsolution products in the stone. On the right side of figure 18, we can see the tiny, dense needles and particles that form both types of stars. In the center of the image we can see much larger, less densely dispersed platelets that resemble confetti.

Keywords

gems, corundum, inclusions.5, Mozambique.12

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G&G Micro-World: Growth tube cluster in sapphire

Hughes, E.B. (2018)

Journal Article · Source: Gems & Gemology · Volume: Vol. 53 · Issue: No. 3, Fall · Pages: pp. 371–372

Abstract

Growth tubes are a typical inclusion in corundum and often seen during examination in the laboratory. While commonplace, a stunning cluster such as the one seen above calls out to the photomicrographer. At the surface these tubes are cut through and some black debris has become lodged inside the ends, while deeper within the stone they still display a fiery glow, reminiscent of rockets launching into the sky. Not only do these tubes spark the imagination, but they can actually tell us a lot about the identity of their sapphire host. The limonitic staining found deeper in the tubes is a yellowish orange, suggesting that they have not been altered by heat treatment. These stains often turn a darker reddish or brownish color in heat-treated stones (J.I. Koivula, “Useful visual clue indicating corundum heat treatment,” Fall 2013 G&G, pp. 160–161). Furthermore, we have observed in the past several months that these prominent growth tubes are a common feature in Madagascar sapphire. While the tubes can be found in corundum from other origins, they seem particularly common in the Madagascar material that has been entering the Bangkok market in greater numbers recently. When taken into account along with other features, they provide a clue to the origin of these sapphires. Thus, what initially appeared to be a mundane inclusion is both visually impressive and gemologically significant, as it provides hints to the origins and treatments of corundum.

Keywords

gems, corundum, sapphire, inclusions.5, Madagascar.12

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G&G Micro-World: Drill hole in heated pink sapphire

Hughes, E.B. (2018)

Journal Article · Source: Gems & Gemology · Volume: Vol. 54 · Issue: No. 4, Winter · Pages: p. 448

Abstract

While testing a faceted pink sapphire in our laboratory, we looked at its internal features and determined that it was a heat-treated stone from Myanmar. As we examined the surface of the 14.75 × 13.02 × 8.82 mm sapphire, we noticed an unusual feature: a large round drill hole extending from the surface into a crystal or negative crystal within the stone (figure 4). Note that this drill hole did not extend through the sapphire, as one might see in a bead. This stone was faceted, so it is unlikely that the person who drilled into the stone intended to create a bead. What seems more likely, given the placement of the drill hole, is that it was drilled to minimize the appearance of the crystal that it reached. We suspect that the crystal was originally more opaque and of darker color or filled with a dark substance. It is possible that the drill hole was created so that the crystal could be cleaned out with acid, minimizing its appearance. We can only guess at the intentions of the treater, who might have gotten the idea from the laser drilling of diamonds. Although the exact process may remain a mystery, this inclusion indicates an unusual treatment in ruby and sapphire.

Keywords

gems, corundum, inclusions.5, Burma.12

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G&G Micro-World: Six-rayed star in sapphire from Myanmar

Hughes, E.B. (2018)

Journal Article · Source: Gems & Gemology · Volume: Vol. 54 · Issue: No. 1, Spring · Pages: p. 71

Abstract

Gems are renowned for their outward beauty, but their in-ternal world can be just as striking. Lotus Gemology re-cently came across a Burmese sapphire, cut as a cabochon and measuring 8.92 × 7.10 × 4.75 mm, that displayed a six-rayed star. Once we examined it under the microscope, we were surprised to find that this celestial theme carried through to the inclusion scene inside (figure 13).

Keywords

gems, corundum, sapphire, Burma.12

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G&G Micro-World: Remarkable twinned calcite inclusion in Mogok ruby

Hughes, E.B. (2017)

Journal Article · Source: Gems & Gemology · Volume: Vol. 53 · Issue: No. 4, Winter · Pages: p. 467

Abstract

The Mogok Stone Tract in Myanmar (formerly Burma) is one of the world’s most famous sources of ruby, which often forms there in a calcite-marble host. Calcite may occur as an inclusion inside the ruby, as in the example in figure 3. In this stone, the calcite is easy to spot between crossed polarizers, which reveal polysynthetic twinning planes that “crisscross” the crystal. While calcite is a common inclusion in ruby, this is the clearest example of calcite twinning this author has seen. Surrounding the calcite crystal is a dense, angular nest of exsolved rutile silk as short needles, a typical scene in rubies from this locality.

Keywords

corundum, inclusions.5, Burma.12, gems

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Ruby & Sapphire • A Gemologist's Guide

Hughes, R.W., Manorotkul, W. and Hughes, E.B. (2017)

Book · Publisher: Lotus Publishing · Pages: 816 pp.

Abstract

From the dawn of time, ruby and sapphire have both attracted and fascinated humans in ways that few other items could. While objects of desire are found throughout the natural world, physical beauty is too often ephemeral. From the allure of a man, woman, flower or butterfly, through the fleeting moments of a sunset, there is little that lasts and practically nothing that can be passed down to our descendants. The exception is precious stones. Not only are they the most durable creations of mother nature, but their visual splendor is truly eternal. In this companion to his 2013 book, Ruby & Sapphire—A Collector’s Guide, Richard Hughes examines these gems from the gemological standpoint, delving into them not just from the aesthetic, but also from the scientific point of view. The product of nearly 40 years of firsthand experience, this book covers the subject from A–Z. History, sources, prices, quality analysis, causes of color, geology, synthetics and treatments—everything is here. Ruby & Sapphire—A Gemologist’s Guide arguably represents the most comprehensive volume ever written on a single precious stone. With over 1000 photos, maps and illustrations and 3500 references, it is nothing less than a tour de force of gemological scholarship.

Keywords

corundum, History.1, Chemistry.2, properties.3, color.4, inclusions.5, treatments.6, synthetic corundum.7, assembled stones.8, fashioning.9, quality.10, geology.11, sources.12, Australia.12, Afghanistan.12, China.12, India.12, France.12, Laos.12, Madagascar.12, Mozambique.12, Malawi.12, Myanmar.12, Pakistan.12, Sri Lanka.12, Tanzania.12, Tajikistan.12, Thailand.12, Vietnam.12, USA.12, Montana.12, gems, irradiation paper on ruby, Indian lapidary, color science, Kashmir, Mogok

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G&G Micro-World: Oiled ruby: A remarkable visual

Hughes, E.B. (2017)

Journal Article · Source: Gems & Gemology · Volume: Vol. 53 · Issue: No. 2, Summer · Pages: p. 244

Abstract

As laboratory gemologists working in Bangkok, we often encounter gems that have been treated with oil to minimize the appearance of fissures. Most of these stones come from Myanmar, where many vendors consider oiling an accepted standard procedure to enhance their goods, particularly ruby and spinel (http://www.lotusgemology.com/index.php/library/articles/315-lotus-gemology-lab-alertfor-oiled-gems). Furthermore, red oil is commonly used not only to improve clarity, but also to enhance the color of the stone (in Chanthaburi, Thailand, it is sold under the brand name “King Ruby Red Oil”). Often this treatment can be identified by flattened gas bubbles in the fissures or by droplets of oil seeping out of the fissures on the surface when the stone is gently warmed by microscope light or hot point. The image above shows a small surface-reaching cavity filled with oil in an unheated 1.75 ct ruby from Myanmar. Unlike other examples we have seen, this remarkable gem contained enough of the filler to easily photograph the striking red color of the oil itself within the cavity. With oblique fiber-optic lighting, a stunning image of this enhancement in situ was made possible, turning even an otherwise commonplace forensic determination into an aesthetic exploration of the micro-world.

Keywords

gems, corundum, ruby, Burma.12, treatments.6, red oil

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Alla scoperta della temperatura perduta, la fluorescenza UV, uno strumento gemmologico

Discovering the lost temperature, UV fluorescence, a gemmological tool.

Hughes, R.W. and Emmett, J.L. (2016)

Journal Article · Source: Traspare: Periodico Tecnico Scientifico · Issue: No. 0 · Pages: pp. 28–33 · Language: in Italian

Abstract

Italian translation of the article “Heat Seeker: UV fluorescence as a gemological tool”

Keywords

gems, corundum, color.4, treatments.6, UV fluorescence

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Padparadscha or pretender: Examination of an unusual pink-orange sapphire

Hughes, E.B., Chankhanatha, C., Burkhardt, A., Manorotkul, W. and Hughes, R.W. (2016)

Journal Article · Source: Australian Gemmologist · Volume: Vol. 25 · Issue: No. 11–12, July–December · Pages: pp. 389–392

Abstract

Abstract: An orangish pink “padparadscha” sapphire was submitted for testing at Lotus Gemology’s Bangkok laboratory. Testing showed a number of con icting features that suggested the gem was a cleverly treated synthetic pink sapphire designed to imitate natural padparadscha.

Keywords

corundum, synthetic corundum.7, gems

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Reviewing the GemmoRaman-532

Hughes, E.B. (2015)

Journal Article · Source: InColor · Issue: Spring · Pages: pp. 28–31

Keywords

gems, gem testing, gemology, instruments, spectrophotometers, Raman

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Inclusion Identification of Burmese Ruby Using Raman Spectroscopy

Vertriest, W., Manorotkul, W. and Hughes, E.B. (2015)

Report · Publisher: GIA/Lotus Gemology · Pages: 59 pp.

Abstract

Project to identify inclusions in ruby from Mogok, Myanmar

Keywords

gems, corundum, inclusions.5, Burma.12

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Let it bleed: New rubies from Madagascar

Hughes, R.W., Manorotkul, W. and Hughes, E.B. (2015)

Web Page · Publisher: Lotus Gemology Co. Ltd. · Volume: 2015 · Issue: 2 September

Abstract

2 Sept. 2015 (updated 28 Sept. 2015) – Recently, a close friend of ours gave us a heads-up about a new ruby mine in Madagascar, sending a photo that showed several pieces of gemmy blood-red ruby rough sitting atop a small scale. Word had it that the Madagascar bush had yielded up yet another piece of crystallized treasure, this twist on terra firma in the form of blood-red ruby. Today rumor became reality. A client walked in with a few dozen faceted rubies. As always, we asked for the source. Mozambique" was the reply. Ho hum. Until I scoped the first piece.Have you ever met someone briefly, and then, after a long period, you glance at a face and think to yourself: "Something's familiar. I think I know you from somewhere." Gazing into the microscope brought back vivid memories of an epic 2005 visit to Moramanga, aka "Sierra Leone," a mine deep in the Madagascar bush. Yes, we had met before."

Keywords

corundum, geology.11, Madagascar.12, gems

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Red Rain: Mozambique ruby pours into the market

Hughes, R.W. (2015)

Journal Article · Source: Journal of the Gemmological Association of Hong Kong · Volume: Vol. 36 · Pages: pp. 39–43

Abstract

23 March 2015—In the autumn of 2007, I spent a month in East Africa, visiting gem dealers and mines in Kenya and Tanzania. The principle aim was to explore the sapphire mines of southern Tanzania at Songea and Tunduru and the spinel mines of Mahenge (described in Downtown) for an updated edition of my book, Ruby & Sapphire, but my team also visited the tanzanite mines at Merelani (detailed in Working the Blueseam). While in southern Tanzania's Tunduru district, we witnessed a number of miners crossing the Muhuwesi river that separates Tanzania from Mozambique. Just a few short months later, it became clear why. Ruby had been discovered in Mozambique. Flash forward to 2009. My close friend, Vincent Pardieu, who I had asked to join me on the 2007 journey, was now working as the GIA's first field gemologist. His job? Hunt down ruby and sapphire, wherever it might be found.

Keywords

corundum, Mozambique.12, gems

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Pleochroism in faceted gems: An introduction

Hughes, R.W. (2014)

Journal Article · Source: Gems & Gemology · Volume: Vol. 50 · Issue: No. 3, Fall · Pages: pp. 216–226

Abstract

While virtually all gemological texts cover pleochroism, it is almost always related to viewing with a dichroscope; exactly how pleochroism manifests itself in faceted gems is largely ignored. This article discusses this phenomenon in doubly refractive gemstones, specifically as it relates to overall color appearance in faceted gems. Contrary to popular belief, pleochroism can be visible in faceted gems even when they are cut with an optic axis parallel to the direction of view.

Keywords

corundum, color.4, gems, color science

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Presidium synthetic ruby identifier

Hughes, E.B. (2014)

Journal Article · Source: InColor · Issue: No. 26, Summer · Pages: pp. 18–23

Abstract

In the lab and marketplace alike, gemologists and gem traders seek to separate natural ruby from synthetic with training and gemological equipment. But what if there was an easier, faster method? Presidium, in collaboration with the Gem and Jewelry Institute of Thailand (GIT), recently released a Synthetic Ruby Identifier (SRI) designed to separate natural ruby from synthetic flame fusion ruby. Bangkok’s Lotus Gemology laboratory was given the opportunity to try out this new instrument to evaluate its utility and accuracy.

Keywords

corundum, color.4, synthetic corundum.7, gems

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Gemological books range from general identification manuals and textbooks to specialized works on individual gems, mineralogy, jewelry, treatments, synthesis, history and gem-producing regions.

For a curated selection of particularly useful books, read The Gemologist's Core Library — Classic Books on Gemology, Jewelry and Mineralogy.

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