English: Citrine was thought to have first been used in jewelry in Greece during the 4th to 1st centuries BC.

Citrine is a variety of crystalline quartz that ranges in color from pale yellow to gold, dark orange, or brown. The golden color is the result of iron impurities in the crystal, and the darker varieties, called Madeira, are considered to be more valuable. Its chemical formula is SiO2. It is a relatively hard stone, with a Moh scale rating of 7, and is therefore quite durable. It has a refractive index of 1.544-1.553, a specific gravity of 2.6-2.7, and a Trigonal crystal structure. The name citrine originated from the French word citron, which means lemon.

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