Citrine (burned) - triple-A, tumbled stones 25-30 mm, Brazil.

Citrine, or lemon quartz, is the lemon-yellow translucent variant of the mineral quartz (SiO₂). Properties Like the other varieties of quartz, translucent citrine is a nesosilicate. The yellow colour is caused by trace elements, in which divalent and trivalent iron play a role. The crystal system of citrine is trigonal, and the hardness is 7. Name: The name citrine is derived from citrus (because of the yellow colour). Depending on the colour, the quartz variety was also called Madeira topaz, golden topaz or Bahía topaz in the past, completely incorrectly, because topaz is a completely different mineral. This was probably done to suggest a higher value. Occurrence The most important sources of citrine are Brazil, Madagascar and the former Soviet Union. Amethyst is often burnt and sold as citrine. You can recognise this material by brown to black points. Citrine is more valuable than amethyst.