Gemmology
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Saturday, 15 August 2026


Gemmology — gemstones — characteristics, classification, specimens, library
Hackmanite

GEMMOLOGY — GEMSTONES

characteristics, classification, specimens, library

As gemstones we accept cut specimens of crystals of natural mineral species having a visible transparency and certain durability. From over 4800 known minerals (according to data of the International Mineralogical Association), approximately 150 satisfy the above conditions and form crystals of sufficient size to be cut.
Characteristics

Colour in gemstones
Clarity in gemstones
Cut in gemstones

Treatment in gemstones

The section ‘Classification’ presents descriptions of 171 different kinds of natural gemstones (106 mineral species). The Nickel-Strunz systematic order (10th edition) is used. Since gemmology does not always follow the systematics of minerals in naming, many popular varieties or just ’names’ are listed.

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List of minerals
Alphabetic list of gemstones
Synthetic stones and simulants
Classification
Featured

Gadolinite-(Y)

— In granite and alkalic granite pegmatites (Anthony et al., 2001—2005). Faceted specimens are extremely rare.
Gadolinite-(Y)
Phenakite
Phenakite
Pyrope
Pyrope
Euclase
Euclase
Andalusite
Andalusite

The section ‘Repository’ contains data and photos of 760 specimens of gemstones. The smallest is just 1.96 mm (0.02 ct) ruby from Mozambique, and the largest — 70.11 mm (326.60 ct) rock crystal from Africa. Besides there are 8 specimens of synthetic stones.

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Repository
Carnelian — specimen 0471

Some exceptional specimens of gemstones from our ‘Repository’

More specimens of gemstones
Ruby — specimen 0318
Agate — specimen 0321
Agate — specimen 0322
Agate — specimen 0325

— More from ‘Repository’

Currently there are 283 bibliographical references and abstracts to publications with gemmological or mineralogical thematics in the ‘Library’. The section comprises also a glossary with 391 terms.
Library
Glossary

cubanite — species of mineral; faceted specimens exist
culet — the bottom end of the pavilion of faceted stone
culet facet — facet at the bottom end of the pavilion of faceted stone; very rare element in the contemporary design
cuprite — species of mineral; faceted specimens reported
Publications

Brögger, W. C., 1890 — Die Mineralien der Syenitpegmatitgänge der südnorwegischen Augit- und Nephelinsyenite, 16. Hambergit — Published in 1890 in ‘Zeitschrift für Kristallographie’; contains the original description of the mineral hambergite.
Damour, A. A., 1883 — Note sur un borate d’alumine cristallisé, de la Sibérie. Nouvelle espèce minérale — Published in 1883 in ‘Bulletin de la Société Minéralogique de France’; contains the original description of the mineral jeremejevite.


Gemmology — gemstones
Front page | Introduction | Classification | Repository | Library

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The specimens illustrated in this site do not exist in the collections of the National Museum of Natural History, Sofia.