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1. Madagascar Sapphire: Low-Temperature Heat Treatment Experiments ...: (Articles); ... they undergo with low-temperature heat treatment in air, which is an oxidizing atmosphere. Introduction to this Madagascar Sapphire Study This study was sparked by a 2017 comment from noted Australian ...; Created on 27 October 2019
2. Gem Treatment Disclosure • Trust • Lotus Gemology ...: (Articles); ... s, too. Value Everyone is taught that gemstones are valuable for three primary reasons – beauty, rarity and durability. Let's consider treatments in light of these factors. The purpose of a treat ...; Created on 04 January 2014
3. Madagascar: Sapphire Isle • Lecture • Tucson, AZ • 6 February 2020: (News); ... ga (a.k.a. Sierra Leone). The lecture also covers the gemology of Madagascar sapphire and ruby, including the most important identifying features, and results from a series of experiments on the heat treatm ...; Created on 26 January 2020
4. FTIR in Gem Testing • A Pink Sapphire Lesson: (Articles); ... Gemology's Bangkok lab for testing. We were asked to test the pink sapphire at the center of each earring. The first gem tested showed inclusion evidence suggesting it had been subjected to heat treatment ...; Created on 21 January 2020
5. World Sapphire Market Update • 2020 • Lotus Gemology: (Articles); ... urma combined. Most of the buying in Madagascar is done by Sri Lankan buyers and as the stones are taken to Sri Lanka for cutting and treatment, many of the blues now sold in Sri Lanka are actually from M ...; Created on 07 December 2019
6. Madagascar Ruby & Sapphire • Ruby & Sapphire: A Gemologist's Guide: (Articles); ... d is suitable for heat treatment. Some pieces are colorless with blue cores; many are strongly zoned. The deposit, in which sapphires are found in altered marble and limestone silicates (‘skarn’), is ...; Created on 18 October 2019
7. Gem Testing Labs • Tips on Choosing a Colored Gem Testing Lab • Lotus Gemology: (Articles); ... e labs are asked to do today is to determine the country of origin and the presence/absence and type of treatments. This requires extensive experience in the field, collecting samples from known localities ...; Created on 21 August 2019
8. Lecture • Madagascar: Sapphire Isle • Luzern, Switzerland • 1 May 2019: (News); ... . The lecture also covers the gemology of Madagascar sapphire and ruby, including the most important identifying features, and some preliminary results from a series of ongoing experiments on the heat treatme ...; Created on 01 May 2019
9. Pressure Heated Sapphire • Squeezing Sapphire • Corundums treated with high temperatures and low pressure (HT+P): (Articles); ... at the question of whether a separate disclosure is needed for the treatment. The following organizations have contributed to and endorse the contents of this article: CGL Central Gem Lab, Japan; CISGEM, ...; Created on 20 February 2019
10. Laos Sapphires • Laos – Land of a Million Elephants... & Sapphires: (Articles); ... size of the gems recovered, the promise was never fully realized. Little serious mining occurred until the 1960s. Like many another sapphire mine, modern heat treatments make salable what was once to ...; Created on 18 February 2019
11. Sapphire With Growth Tube Cluster • Sapphire Inclusions: (Articles); Surface-reaching growth tubes in a sapphire provide insight into the gem’s origin and treatment history. Surface-reaching growth tubes within a sapphire exhibit unaltered yellowish staining, an indication ...; Created on 23 February 2018
12. Oiled Ruby: A Remarkable Visual • Ruby Inclusions: (Articles); ... 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 ...; Created on 23 February 2018
13. Lecture • Madagascar: Sapphire Isle • Tucson • 31 January 2018: (News); ... s on the heat treatment of Madagascar sapphire. When 31 January 2018 Where 2018 Accredited Gemologists Association Tucson Conference Tucson University Park Hotel Conference Center 880 E. Second Stre ...; Created on 31 January 2018
14. Lecture • Ruby Inclusions • Sweden • 17 June 2017: (News); ... are ruby treatments and how to identify them. When 17 June 2017 Where Scandanavian Gem Symposium Sweden ...; Created on 17 June 2017
15. Gem Inclusion Pairs • Hyperion Siamese Twins: (Articles); ... fissures between the individual crystal grains that make up the jade rock. These fissures are then filled with a polymer. Thus the treatment removes brown discoloration and greatly improves the translucency. ...; Created on 29 January 2016
16. Inclusions in Gemstones • Hyperion Literature Sources: (Articles); ... ngshield, R. and Nassau, K. (1981) The heat and diffusion treatment of natural and synthetic sapphires. Journal of Gemmology, Vol. 17, No. 8, Oct., pp. 528–541; RWHL*. Du Toit, G., Hughes, R.W. et al. ...; Created on 22 January 2016
17. Ruby From Madagascar • Let It Bleed • Lotus Gemology: (Articles); ... often a strong indication of artificial heat treatment, was absent. This, along with the inclusions, suggested that all the stones submitted had not been subjected to heat treatment. Some specimens sh ...; Created on 28 August 2015
18. Gem Enhancements Explained • Lotus Gemology: (Lab); ... treatments which are detected. Our approach is to give our customers the same information we would want when purchasing a gem. The following tables explain the enhancement terminology as given on Lotus ...; Created on 14 May 2015
19. GemmoRaman-532 • Instrument Review • Lotus Gemology: (Articles); ... than ever. With treatments become increasingly sophisticated, gemologists and traders search for new tools to help identify stones. How does one make the call on a completely clean spinel, with no ...; Created on 20 March 2015
20. Oiled Gems Lab Alert • Lotus Gemology: (Articles); ... decide what is and is not acceptable in terms of treatments. Certainly there is a place in the market for natural, treated, synthetic and imitation stones. That said, we have had a string of clients who ...; Created on 09 March 2015

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