citrina

Citrine is yellow to orange-yellow quartz — macrocrystalline silicon dioxide colored by trace iron impurities — that has been used as a gemstone since antiquity but only acquired its modern English name in the 16th century. The word descends from Medieval Latin citrina (lemon-yellow, of the color of citrus), from citrus — the Latin name for the citron tree (Citrus medica) and its fruit, which gave its name to the entire citrus genus. The Latin citrus itself is borrowed from Greek kitron, which was probably taken from an unknown Near Eastern language; some etymologists propose a connection with Hebrew etrog (the citron used in the Feast of Tabernacles) or with an unknown Semitic source. The eventual root of citrine, traced back far enough, disappears into the ancient Near Eastern origin of the citrus fruit itself, which was domesticated in South or Southeast Asia and spread westward.

For most of recorded history, citrine was confused with or used as a substitute for topaz — the two stones share a yellow color range and are both transparent, and in the absence of modern mineralogical analysis there was no obvious way to distinguish them without test-cutting. Medieval and Renaissance gem literature is full of references to 'yellow topaz' that, when surviving examples are analyzed, prove to be citrine. The confusion was commercially convenient: genuine yellow topaz from the Ural Mountains or Brazil was rare and expensive, while citrine — found in abundance in the quartz veins of Spain, Scotland, Brazil, and Madagascar — was far more common. The fraudulent substitution was widespread enough that Pliny cautioned buyers against it, and the confusion persists in popular usage even today, with 'topaz' still incorrectly applied to yellow quartz in some commercial contexts.

The Scottish deposits of citrine — found in the Cairngorm Mountains and along Highland riverbeds — gave the stone the alternative name 'Cairngorm' in Scottish tradition, and citrine became closely associated with Highland dress and Celtic jewelry from the 17th century onward. The large cairngorm stones set in the handles of Highland sgian-dubhs (the small blade worn in the stocking), in brooches, and in sporran mounts gave citrine a specific cultural identity in Scottish craft tradition that the more generic name 'citrine' does not fully convey. Queen Victoria's enthusiasm for Scottish Highland aesthetics during her Balmoral years (from 1852 onward) brought cairngorm citrine jewelry to wider fashionable attention, and the Scottish gem trade benefited accordingly from royal endorsement.

The 20th century created a second variety of citrine that requires explanation: heat-treated amethyst. When amethyst — the purple variety of quartz — is heated to temperatures between 470 and 560 degrees Celsius, the iron impurities responsible for its purple color reconfigure into the iron oxide form that produces yellow, producing a stone virtually identical in appearance to natural citrine. This heat treatment has been practiced commercially since at least the 1930s and is now the source of the majority of commercial citrine on the market. The technique is disclosed in reputable gem trade practice but not always in popular retail. The result is that 'citrine' in the modern gem market encompasses both naturally colored yellow quartz and thermally converted amethyst, which are mineralogically the same mineral but geologically different products.