Tourmaline Loose Gemstones

Tourmaline is the US National Gemstone.  It comes in a variety of colors and related minerals as Tourmaline is it's on gemstone family.   You can also find Gemstone optical property chatoyancy as part of the mix.  Tourmaline belongs to the Trigonal crystal system and ranks 7 to 7.5 on Mohs hardness making it a quite durable gemstone.