Apatite means cheat in greek because it can be easily confused with many other gemstones the most common of which today for the blue would be Zircon. It is availible in blue and also green, pink and yellow and also violet the light green of this is called asparagus stone due to the colour. This gem is found in many depsoits worldwide and is commanly availible. It has a mohls hardness of 5 and a refactive index of 1.628-1.649.