Citrine

Group: Quartz Mineral class: Oxides Colour pale to dark yellow, brown, reddish-brown Colouring substance: iron Pleochroism: weak. Only in natural Citrins. Pale yellow, yellow Mohs’ hardness: 7 Density: 2.65 Cleavage: absent Fracture: conchoidal, very brittle Crystal system: trigonal, 6 faced prisms, pyramids Transparency: transparent Lustre: vitreous lustre Fluorescence: almost none

Its name comes from its colour, similar to oranges or lemons. Natural Citrins are rare. Many are achieved by heating up lower quality amethysts (turns into pale yellow at 470C and into dark yellow and brown at 550-560C) or smoky quartz (turns into yellow-brown at 300-400C). Almost all the Citrins, which come from the heating of a gemstone, are slightly reddish. Natural Citrins are usually pale yellow.

Natural Citrins are found in Brazil, Madagascar, USA, Argentina, Burma, Namibia, Russia, Scotland and Spain.

Good Citrins, which can be cut with facets are very rare, as they need to have an optimal transparency and even colour. Inclusions shouldn’t be seen except with a magnifying glass. A good Citrine can be cut in any way. It can even be sculpted into little figures.

With many other yellow stones, especially with beryl, topaz and tourmaline.