The following information is from website: http://en.wikipedia.org/wiki/Quartz
Citrine is a variety of quartz whose color ranges from a pale yellow to brown. It is nearly impossible to tell cut citrine from yellow topaz visibly. Citrine has ferric impurities, and is rarely found naturally. Most commercial citrine is in fact artificially heated amethyst or smoky quartz. Brazil is the leading producer of citrine, with much of its production coming from the state of Rio Grande do Sul. The name is derived from Latin citrina which means "yellow" and is also the origin of the word "citron."[9]
Citrine is one of three traditional birthstones for the month of November.
The hardness : 7 or lower
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