Turquoise The name means Turkish stone as this was the route into Europe. Pure blue colour is very rare as most is interspersed with other elements or intergrown with malachite or chrysocolla. It is found in widespread depsoits but the best quaility is said to come from north east Iran. This gem is very easy to damage so is bets taken off when washing etc as this will effect the colour. House hold chemicals such as cleaners and deturgents should be avoided. It has a mohls hardness of 5-6 and a refractive index of 1.610-1.650