CLARITY SCALE IF VERY HIGH QUALITY & FREE FROM INCLUSIONS. VVS HIGH QUALITY WITH VERY SLIGHT INCLUSIONS. VVS1 HIGH QUALITY WITH SLIGHT INCLUSION. VS FINE QUALITY WITH INCLUSION SLIGHTLY VISIBLE TO THE NAKED EYE. VS1 FINE QUALITY WITH INCLUSION VISIBLE TO THE NAKED EYE. SI GOOD QUALITY WITH INCLUSIONS VISIBLE TO THE NAKED EYE. SI1 INCLUSIONS BECOMING PROMINENT TO THE EYE. I INCLUDED.
Name Tourmaline Chemical Structure (Li,Na,Ca)(Fe,Mg,Mn,Al) 3(Al,Fe)6(BO3)3Si6O18(OH,F)4 AluminumBoroSilicate (wide variety of substitutions)
Scientific Properties: Mohs Hardness of 7.5 with a trigonal crystal structure. Members of the tourmaline family of minerals have basically the same crystal structure, but occurs in many colors, each with their own name.