a - SiO₂

MINERAL: Transparent Quartz or rock crystal.

ORIGIN: Madagascar.

CHEMISTY FORMULA: a - SiO₂

STRUNZ GROUP: Tectosilicates.

GENESIS: It forms on igneous, metamórfic and sedimentary rocks, being able to find in pegmatitic, neumatolitic and hidrothermal veins with metallic menas or single.

UTILITY: Very important in gold and silver work and for the construction of quartz clocks.

LOCALIZACION IN THE MUSEUM: Display cabinet 17

ETIMOLOGY: The name of the quartz comes from the Greek word " Kristallos " that means ice. This was thus because old the Greeks thought that the quartz was congealed water so intensely that no longer it was impossible to be defrost. This idea lasted until century XVII.

OBSERVATIONS: The crystalline quartz, presents many more varieties, of which some also are precious stones or gems like:

Blue-violet Quartz or Amethyst = > its color is due to the iron oxide presence in its interior.
Transparent quartz = > also call rock crystal.
Yellow quartz or citrino = > is looked like the topaz.
Rutilated quartz or sagenite = > also call quartz sapphire, is crossed by needles of rutilo in the interior of the quartz crystal.
Quartz black or smoked = > also call quartz morión , and must to the damage poducido by radioactivity.
Green quartz or prasio = > has actinolita within its structure.
Bloody or red quartz = > also call jacinth of Compostela, has iron in its interior in oxide form.
Quartz cat eye = > of green color with asbestos fibers in its interior.
Quartz tiger eye = > of yellow-blue with fibers of crocidita in its interior.
Pink quartz = > with impurities of manganese and titanium in its interior.
White or milky quartz = > Tiene in its interior many microscopic inclusions and hollows.

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Updated: February of 2001. Pages processed and maintained by E. Hernandez Torrego