What is Citrine?
Citrine is the yellow to orange variety of quartz, valued for its warm colour, good durability and transparent crystals or faceted gems.
Mineralogy and structure
The reference formula is SiO2. Citrine belongs to the silicates and has a trigonal crystal system. Citrine is a quartz variety, not a separate mineral species, so it uses the trigonal quartz structure. Natural citrine should be distinguished from heat-treated amethyst by locality, colour zoning and mineralogical context.
Colour and appearance
Typical colours include yellow, golden yellow, yellow-orange, orange. Crystal habit, lustre, transparency and matrix association are often as diagnostic as colour.
Formation and localities
Citrine forms in or is associated with silica-rich hydrothermal veins, pegmatites and cavities where trace iron and irradiation influence the quartz colour. Important documented localities include Brazil, Madagascar, Spain, Russia, Uruguay and selected localities in the United States.
Collecting and care
Citrine is best kept as a labelled collector or reference specimen. Protect fragile crystals from impact and prolonged humidity changes. Lead-, arsenic-, chromium- and cobalt-bearing minerals should not be cut, ground or used in jewellery.
