Product Name: Silicon nitride alpha Purity: >99.99% [Cu, Cr, Co, Na, W, Fe, Zn, Mg, V] <0.0001 [Al, Ni]: 0.0002 SSA: 20m2/g Crystal Form: alpha Color: White APS: 0.5um-1um Hazard class: None Because of the anti high temperature property, silicon nitride can be used as release agent successfully. It can prevent the adhibitting of melting silicon and crucible and also can obstruct the silicon and crucible so that guarantee the purity of silicon. We can control the granularity under the condition of different needs.