Turquoise is a blue-green copper-aluminium phosphate, soft (5 to 6 on the Mohs scale), which tradition links to protection and luck. Porous and often treated, it calls for care when buying. Here's what it is and how to choose it.
Turquoise is a copper-aluminium phosphate, sky-blue to blue-green, often crossed by fine brown veins (the "matrix"). It is soft and porous (hardness 5 to 6), so sensitive to water, oils and cosmetics, which can turn it green. Many turquoises are stabilised (resin-impregnated) to harden them — acceptable if disclosed.
In crystal tradition, turquoise is a stone of protection and luck, worn for millennia by many cultures. These virtues are traditions and beliefs: they are not scientifically demonstrated and replace no medical advice (see sources).
Porous, turquoise is best kept for protected wear (pendant, low-exposure ring) and away from water, perfume and creams. Beware: cheap, bright-blue "turquoise" is very often dyed howlite (see our howlite article). See also our natural stone jewellery guide.
A dry or barely damp soft cloth, no soaking, chemicals or ultrasonics. Remove it before showering, the pool and applying cosmetics.
Tradition links it to protection and luck. These virtues are beliefs, with no scientifically demonstrated effect, and replace no medical advice.
Real turquoise often shows a matrix (fine brown veins) and a nuanced blue-green. A bright, uniform, cheap "turquoise" is very frequently dyed howlite or reconstituted turquoise.
No: soft and porous, it dislikes water, soap, perfume and cosmetics, which can turn it green. Remove it before showering, the pool and applying creams.
Compare the jewellers in your city on verifiable criteria.
See the rankings