Is it Green Garnet Sand?
In the market, exactly only in China,there is a nutural mineral sand,appear green color,with the same applications with garnet sand: sandblasting and waterjet cutting.
Most users calls it green garnet sand,but in fact it is different from garnet sand,it is Omphacite.
First the pictures are as follows:
Then what is Omphacite?
Chemical Composition
Silica SiO2………………………………54-58%
Iron(Fe2O3+FeO)……………………….3-5%
Alumina Al2O3………………………….12-14%
Magnesium MgO…………………………5-7%
Calcium CaO………………………..….…8-11%
Manganese MnO………………………….0-1%
Sodium oxide Na2O………………………6-8%
Physical characteristic
Specific Gravity…………………………. 3.29-3.37g/cm3
Hardness………………………………….Mohs 6.6-6.8
Chloride content less than 15ppm（25ppm max）
Colour………………………………………Green
Acid solubility(HCL)less than 1%
Conductivity less than 25 ms/m
Melting point………………………………1100℃
Grain shape…………………………………sub angular
Mineralogical Composition
Omphacite………………..…………………. >85%
Almandite Garnet……………………………. <15%
Ilmenite………………………………….……<0.5%
TiO2………….. ………………….…………… <0.5%
Omphacite has the same application with garnet sand,but it has better price than garnet sand.
