Running a bit late with this Gem of the Month article but this cheerful gemstone is worth waiting for – better get a move on or it will be time to do the gem for December. Citrine is a very popular gem and is listed as the modern birthstone for November along with the much more difficult to find Golden Topaz.
As might be guessed from the name, citrine comes in a range of citrus colours ranging from lemon yellow, gold to the rich orange of a fine madeira. This affordable gem is ideal for a variety of uses as it is usually very clean, without inclusions and available in large sizes. For these reasons, citrine is often used by specialist cutters for custom shapes or new faceting techniques as seen in the concave faceted gem at left (image from Gem-by-Gem article).
Gemmology matters: Citrine is a macrocrystalline variety of quartz (SiO2) and is not the more valuable topaz. Citrine, like all quartz has a hardness of 7 . Ctrine has a hexagonal crystal system with no cleavage, vitrous lustre and conchoidal fracture.
Citrine may be found naturally but almost all commercially available citrine is heat-treated amethyst (much of it mined in Brazil). Good quality citrine found in its natural form is relatively rare. The color of citrine is due to trace amounts of iron impurities within the crystal structure – the difference between citrine and amethyst is only the oxidation state of these iron impurities. Heating amethyst reduces the oxidation state of the iron impurities and causes the purple colour of amethyst to fade and become yellow to reddish-orange (citrine). Care should be taken to avoid scratches/damage and prolonged exposure to sunlight and extreme heat.
Mythology and Lore: In ancient times, citrine was carried as a protection against snake venom and evil thoughts. It is said to promote creativity and intuition, help personal clarity and eliminate self-destructive tendencies. Citrine is also said to be very helpful in assisting one to acquire and maintain wealth. Citrine is the zodiac stone for the sign of Virgo and the anniversary gemstone for the 13th and 17th years of marriage.
Alternatives in yellow: There are a number of alternative gemstones with the range of yellows and oranges found in citrine. All of these have their advantages but are generally more expensive than citrine. Yellow or orange sapphire is readily available now at reasonable prices – while sapphire has the benefit of increased hardness (9), buyers should be aware that much of this yellow/orange material has been Beryllium treated (bulk or lattice diffusion). Fully natural yellow sapphires of good quality are much more rare and a price premium exists for these types – ideal for those wanting something really special.
Yellow and orange gems are also available in tourmaline, fire opal, topaz, garnet (spessartite, hessonite, etc) and beryl (heliodor or golden beryl). Of course, diamonds are also found in shades of yellow, champagne or orange – these are termed fancy diamonds and the colour may be natural or the result of some treatment process. There is often a large price differential between gemstones of natural colour and where colour is enhanced or altered by treatment so please insist on full disclosure on treatment status before any significant purchase.
Thank you for your interest. The December Gemstone of the Month article will appear shortly.
Cheers for now from Aussie Sapphire