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The Rock Professor has provided you with a mineral
information card. Print on stock paper, and cut out to
enhance your rock and mineral products.
To print: with your cursor, highlight the entire card below,
right click and select print, then click on "selection"
and print.
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THE ROCK PROFESSOR
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CITRINE
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Citrine is a light yellow to yellowish-brown variety of QUARTZ. Natural citrine is colored by trace amounts of ferric hydroxide. Most of the citrine on the market is actually heat-treated amethyst or smoky quartz.
As in other varieties of quartz, citrine has a hardness of 7, a specific gravity of 2.65, and chemically, is SiO2. It has a vitreous luster and belongs to the hexagonal crystal system.
When amethyst is heated to approximately 500-600 degrees C, a yellowish-brown citrine color is produced. Not all amethyst responds in like fashion. Most of the Brazilian citrine on the market comes from the Irai region of Rio Grande do Sul.
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Chemistry: SiO2 ♦ Variety: quartz ♦ transparent to translucent ♦ Luster: vitreous ♦ Crystal system: hexagonal ♦ Moh's hardness: 7 ♦ Color: yellow to orange ♦
Localities: world-wide, but principally Brazil
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