How to identify the tourmaline stone

Natural tourmaline stone had three forms.

1, Single crystal is cylindrical, ranging in length, there were six edges, there are three edges, some black, brightness, density stone slightly larger than normal, with the fur friction will adsorption light small objects.

2, Fibrous, acicular, bundle of tourmaline, black, with the light.

3, Tourmaline crystals, patches, also with brightness, density is larger than general stone.

These three forms tourmaline stone just come from different area but from washing, drying and crashing to tourmaline  powder 100mesh, 200mesh, 325mesh, 600mesh, 800mesh, 1250mesh, 2000mesh, 3000mesh and 6000mesh. Had same effect for our use.