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Chemical Formula | SiO2 | ||||||
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Composition | Silicon dioxide | ||||||
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Color | Yellow, yellow-brown, orange, dark orange-brown, reddish-brown | ||||||
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Streak | White | ||||||
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Hardness | 7 | ||||||
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Crystal Forms and Aggregates |
(Hexagonal) Most commonly occurs as protruding cluster of pyramids on a geode base. Also occurs as short, stubby, terminated crystals, either singular or in drusy aggregates. Also occurs massive and crusty. | ||||||
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Transparency | Transparent to translucent | ||||||
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Specific Gravity | 2.6 - 2.7 | ||||||
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Luster | Vitreous | ||||||
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Cleavage | Indiscernible | ||||||
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Fracture | Conchoidal | ||||||
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Tenacity | Brittle | ||||||
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Other Names | Citrine closely resembles Topaz. Unfortunately, unscrupulous
dealers have adapted false name for Citrine so unaware
buyers think they are buying more valuable Topaz. It
should be known that any "Topaz" labeled with a
prefix name (such as Gold Topaz, Madeira Topaz, False
Topaz, Brazilian Topaz, and Citrine Topaz) is heat-treated Citrine. However, there are three
exceptions: Imperial Topaz Oriental Topaz Precious Topaz |
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Varieties |  Ametrine - Mixture of Amethyst and Citrine. It is partially
purple and partially orange-yellow. |
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In Group | Silicates ; Tectosilicates ; Silica group May also be classified as an oxide (Oxides ; Simple Oxides) |
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All About | Citrine is a yellow to brown variety of Quartz. It is widely used as a gem, and
is the most valuable Quartz gem. Almost all Citrine on
the market is heat-treated Amethyst. Natural Citrine is yellow to
orange, and occurs in much lighter hues than the
heat-treated material, which is dark orange-brown to
reddish-brown. In some Amethyst deposits, the Amethyst
has been partially or fully changed to brown Citrine by
natural means of heating, thereby transforming it into
Citrine. Citrine may also be produced by heat-treating
Smoky Quartz from certain localities. All heat-treated material has a red tint, whereas the natural specimens do not. |
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Uses | Citrine is known mainly for its use as a gem. Gems are faceted for jewelry, and are sometimes used as a substitute for Topaz. Citrine is also popular among mineral collectors. | ||||||
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Striking Features | Color and crystal habits | ||||||
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Popularity (1-4) | 1 | ||||||
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Prevalence (1-3) | 3 | ||||||
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Demand (1-3) | 1 | ||||||
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Distinguishing Similar Minerals |
Topaz - harder (8), has perfect cleavage Chrysoberyl - harder (8½) Apatite - softer (5) Fluorite - much softer (4) Heliodor (Beryl) - harder (7½ - 8), crystals are usually different (more elongated and perfect hexagons) |
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Commonly Occurs With |
Amethyst, Agate | ||||||
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Noteworthy Localities |
Natural Citrine is not common and occurs
sparingly in many large Quartz deposits. Most material
comes from Minas Gerais, Brazil, but almost all of the
Brazilian material is heat-treated Amethyst. Citrine can be found in the Ural Mountains of Russia, in Dauphine, France, and in Madagascar. |
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Picture Icon Links |
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Picture Links | 1. Orange Citrine crystals 2. Brownish-red crystal cluster 3. Natural yellow Citrine crystals with Amethyst |
