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Tsarstone collectors guide

Gemological Institute of America

Provides grading and identification of diamonds, coloured stones or pearls for the industry and consumers.

GIA New York
Homepage Address Contact 580 Fifth Avenue
Suite 200
New York 10036
United States of America
N: Jan Tilton
T: 212-221-5858
F: 212-575-3095

GIA is considered the world's most trusted name in diamond grading and gemstone identification. GIA’s D-to-Z colour-grading scale and Flawless-to-I3 clarity-grading scale are recognized by gem and jewellery professionals everywhere. And, by extension, the GIA Diamond Grading Report, Diamond Dossier, and Gemological Identification Report are considered the world’s premier gemological credentials.

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Multicolour Gems
Specializing in African colored gemstones including alexandrite, Madagascar sapphire and tanzanite. Also includes general information about gemstones and gemological articles.
Designer of fine jewellery with natural alexandrite
Offers pearl jewellery with alexandrite, couture jewellery collections and bespoke jewellery service.
David Wein
An online fine jewelry store offering one off pieces of alexandrite and collector stone jewelry, custom jewelry service and rare gemstones sourcing.
David Yurman
The official David Yurman online store features collections of fine jewelry, timepieces and gifts for women and men from America's premier jewelry designer.
Gem Studies Lab
Gem Studies Lab The Gemmological Association of Australia (GAA) is Australia’s historic trade-accepted non-profit educational authority for gemology.
European Gemological Laboratory
Provides identification for rough and polished diamonds, colourless and coloured diamonds, as well as coloured gems and pearls.
Hong Kong Gems Laboratory
Provides identification and appraisal reports for rough and polished jade, colour gemstones and pearls.
One of the most authoritative gemmological laboratory offering gemmological analysis using the latest equipment.
The Russian MSU Gemological Center
Issues four types of identification reports in two formats, including Diamond Report, Gemstone Testing Report, Jewelry Report and Rough Diamond Report.
AIGS Gemological Laboratory
Well known laboratory for its expertise in coloured gemstones, especially ruby, sapphire, emerald, jade and rare stones. Also provides identification and grading services for diamonds and jewellery.
The Gem and Jewelry Institute of Thailand
Offers authenticity of gemstones and their treatment reports, identification of pearls and their treatments, diamond grading and laser inscription on diamonds and colour gemstones.
GemResearch Swisslab
Determination of the authenticity and country of origin of rubies, sapphires and other rare colour gemstones. Also offers gemstone reports and inscriptions.
Gubelin Gemological Laboratories
An independent member of the Gubelin Holding and one of the world's most respected laboratories, offers gemstones, diamond and pearl reporting.
An independent, international, non-profit organization dedicated to the identification, treatment and origin of gemstones.
AGTA Gemological Testing Center
Provides identification and origin reports and other colour gemstone services, including testing for beryllium in sapphire, natural origin of colour in diamonds and country of origin for sapphires, rubies and alexandrites.
American Gemological Laboratories
Provides independent coloured gemstone identification reports on all coloured gemstones including emeralds, rubies, sapphires and alexandrites.
Gemmological Association of Great Britain
Services include reports for diamond grading, pearl and gem identification. Also provide re-polishing diagrams for diamonds and verbal assessments for diamond colour and clarity
Jewellers Vigilance Canada (JVC)
An independent, non-profit association to advance ethical practices within the Canadian jewellery industry.
The National Association of Jewelry Appraisers
Conducts various programs designed to serve the interests of both its members and the public at large in matters relating to appraisal theory and valuation science.
The International Society of Appraisers
A non-profit association includes respected independent appraisers, consultants, estate liquidators, auctioneers, gallery owners, and dealers.
The American Society of Appraisers
An organization of appraisal professionals and others interested in the appraisal profession, representing all of the disciplines of appraisal specialists.
National Association of Goldsmith
Supports National Association of Goldsmiths' Registered Valuer Scheme. All N.A.G. Registered Valuers throughout the United Kingdom have proved their expertise and with formal gemological qualifications and substantial experience within the industry.
The Association of Jewellery Appraisers
Provide the general public with a source of jewellery appraisers with high standards of accuracy, presentation, ethics and integrity.
Embassy Emeralds
Online dealer of fine, cut Colombian emeralds in a variety of shapes, including emerald cut, oval cut, and fancy cut emeralds.
China Stone
Sells precious and semi-precious gemstones in calibrated and free form sizes. Also precision machine-cut sapphires and rubies featuring perfect symmetry and polish.
Offers over 150 gemstone varieties, including loose stones, pearls, cameos, carvings, cabochons, faceting rough, rare minerals and natural crystals
Pala International
Wholesale precious and semi-precious gemstones to trade members only. Also features educational articles on all aspects of gems, gemology and mineral specimens.
Retails most gemstone varieties. Also includes general information about the gemstones and comprehensive guide to emeralds
Diamnd Tech
Produces grinding wheels, saw blades, special form wheels, and diamond discs in a complete range of sizes specializing in lapidary products.
Colored Stone
Bimonthly, international trade magazine that covers all facets of the colored gemstone industry, including new sources for colored gemstones, mining and processing, retail sales, consumer buying trends and technological developments pertaining to the trad
The International Colored Gemstone Association
An independent non-profit association that was founded in 1983 to represent the international gemstone industry
The Gem Guide
Provide accurate and reliable gemstone pricing and reference information to the industry.
American Gem Trade Association
A group of US and Canadian professionals dedicated to promoting the natural colored gemstone and cultured pearl trade
The Weinman Mineral Gallery
Features gemstones, minerals and fossils. Includes virtual tour, special events, hours, prices and directions.
Colburn Earth Science Museum
Primary collection includes some 4,500 specimens and gemstone collection includes over 1,000 cut gemstones from North Carolina and around the world
Synthetic Gems
Offers large selection of synthetic padparadscha sapphire, lab alexandrite, created and synthetic lab emerald, cubic zirconia (CZ), white clear lab sapphires, lab-grown citrine quartz, and synthetic ruby.
Mark Henry
An exclusive designer of natural alexandrite jewelry. Famous for decadent designs and superior quality fine jewelry pieces.
A collaborative effort among multiple societies to place the world's most comprehensive collection of mining and minerals based research in one place.
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