Lotus • Articles from Lotus Gemology
Pressure Heated Sapphire | Corundums treated with high temperatures and low pressure (HT+P)
Pressure Heated Sapphire | Corundums treated with high temperatures and low pressure (HT+P)
- [see below for authors]
27 February 2019: Sapphires heated with high temperatures and low pressures (~1kbar) first entered the market in 2009, becoming more common since 2016. This article examines the process in detail and looks at the question of whether a separate disclosure is needed for the treatment.
Lao Sapphires | Laos – Land of a Million Elephants... & Sapphires
Lao Sapphires | Laos – Land of a Million Elephants... & Sapphires
- Richard W. Hughes, Auslan Ishmael, Flavie Isatelle & Peter Wang
The history of the Lao sapphire mines at Ban Huay Xai is detailed, along with modern mining by Hong Kong based Sino Resources Mining Corp. Ltd. from 2006–2012.
Colored Stone Grading | A Heretic's Guide
Colored Stone Grading | A Heretic's Guide
- Richard W. Hughes, with E. Billie Hughes & Wimon Manorotkul
Developing a comprehensive colored stone grading system has been the dream of gemologists since the late 1970's, but despite a number of valient attempts, we are no closer to the goal today than we were four decades ago. This article examines the various problems of colored stone grading, explaining why the challenges are at least an order of magnitude greater than the grading of diamonds.
Six-Rayed Star in Sapphire from Myanmar
Six-Rayed Star in Sapphire from Myanmar
- E. Billie Hughes
A Burmese sapphire shows a celestial scene both externally and internally.
Mogok Ruby With Remarkable Twinned Calcite Inclusion
Mogok Ruby With Remarkable Twinned Calcite Inclusion
- E. Billie Hughes
An included calcite crystal within an unheated Burmese ruby displays dramatic twinning planes.
Sapphire With Growth Tube Cluster | Sapphire Inclusions
Sapphire With Growth Tube Cluster | Sapphire Inclusions
- E. Billie Hughes
Surface-reaching growth tubes in a sapphire provide insight into the gem’s origin and treatment history.
Oiled Ruby | A Remarkable Visual
Oiled Ruby | A Remarkable Visual
- E. Billie Hughes
A ruby’s surface-reaching cavity is filled with red oil.
Crystal Optics with the Refractometer
Crystal Optics with the Refractometer
- Richard W. Hughes
The optical properties of crystals are intimately related to their crystal structures. This article examines the precise relationship between optic character and sign and crystal structure.
A Sapphire's Secret | Synthetic Yellow Sapphire
A Sapphire's Secret | Synthetic Yellow Sapphire
- E. Billie Hughes
At the Lotus Gemology laboratory in Bangkok, we often get parcels of relatively uniform stones. But sometimes it is in this routine testing that we uncover surprises.
Spinel Inclusions | Beyond Octahedra
Spinel Inclusions | Beyond Octahedra
- E. Billie Hughes
A look into the world of spinel inclusions that goes beyond simple octahedral crystals.
Ruby & Sapphire (Corundum) Inclusions | The Lotus Gemology Crystal Registry
Ruby & Sapphire (Corundum) Inclusions | The Lotus Gemology Crystal Registry
- E. Billie Hughes and Richard W. Hughes
Solid inclusions have been used by gemologists as a means of determining origin. While there is a great deal of overlap from one source to another, there are also important differences. For example, while apatite has been identified in sapphire from Madagascar, Myanmar and Sri Lanka, apatite has never been identified in sapphire from Kashmir. Thus the purpose of this article is to give a full listing of solid inclusions in gem corundums from around the world, with each occurrence fully referenced. This is provided with the goal of making origin determination of ruby and sapphire more accurate.
Padparadscha or Pretender | An Unusual Pink-Orange Sapphire
Padparadscha or Pretender | An Unusual Pink-Orange Sapphire
- E. Billie Hughes, Chawalit Chankhantha, Andreas Burkhardt, Wimon Manorotkul & Richard W. Hughes
An orangish pink “padparadscha” sapphire was submitted for testing at Lotus Gemology’s Bangkok laboratory. Testing showed a number of conflicting features that suggested the gem was a cleverly treated synthetic pink sapphire designed to imitate natural padparadscha.
จากพีค็อกบลูถึงสีเลือดนก • นิยามแห่งสีจากโลตัสเจมโมโลจี
จากพีค็อกบลูถึงสีเลือดนก • นิยามแห่งสีจากโลตัสเจมโมโลจี
- Lotus Gemology
บทคัดย่อเรื่องการจำแนกสีทับทิมและแซฟไฟร์ ที่ใช้ในโลตัสเจมโมโลจี
Inclusions in Gemstones | Hyperion Literature Sources
Inclusions in Gemstones | Hyperion Literature Sources
- Lotus Gemology
For those who wish to explore the literature of inclusions in gemstones further, we have selected the following articles and books that are of particular merit. Most of these are cited in the Lotus Gemology Hyperion Inclusion Database, and all can be found in our full Four Treasures Reference Database, but are listed below in a more convenient summary format. Many of the links will allow you to download a PDF copy of the original article.
Lotus Gemology Report Lookup Guide
Lotus Gemology Report Lookup Guide
- E. Billie Hughes
The best way to check the authenticity of a Lotus report is with online report verification.
从孔雀蓝到鸽血红 细数宝石之美 • 红蓝宝石之动人色泽
从孔雀蓝到鸽血红 细数宝石之美 • 红蓝宝石之动人色泽
- Richard Hughes
Chinese-language translation of Lotus Gemology's ruby and sapphire color types.
Ruby From Madagascar | Let It Bleed
Ruby From Madagascar | Let It Bleed
- Richard W. Hughes, with Wimon Manorotkul & E. Billie Hughes
When it rains red, it doesn't simply pour. It bleeds. Following closely on the heels of the ruby strikes in Mozambique, a major new find of the crimson stone is made in Madagascar.
Dana Schorr | In Memoriam
Dana Schorr | In Memoriam
- Richard W. Hughes
Gem dealer, world traveler, activist, Dana Schorr passed away on 5 August 2015 at age 63, following a heart attack.
Ruby & Sapphire Color Types | From Peacock to Pigeon's Blood
Ruby & Sapphire Color Types | From Peacock to Pigeon's Blood
- Lotus Gemology
A brief description of the color types for ruby and sapphire used at Lotus Gemology.
Mozambique Ruby | Red Rain Pours into the Market
Mozambique Ruby | Red Rain Pours into the Market
- Richard W. Hughes
Is the Mozambique stone the bejesus of bird's blood? Lotus Gemology's resident ruby wallah, Richard Hughes, weighs in on the state of the market and how Mozambique stacks up to historical heavyweights like Burma and Thailand/Cambodia.