CAS 12033-89-5 appears in our catalog under these names: Silicon(IV) nitride, 99.3% (metals basis), typically 90% ^b-, Silicon(IV) nitride, amorphous, nanopowder, 98.5+% , Silicon(IV) nitride, Electronic Grade, 99.85% (metals basis), Silicon(IV) nitride, ^a-phase, 99.9% (metals basis) , Silicon(IV) nitride, alpha-phase, ca. 90% . Offered by: Thermo Scientific (Alfa Aesar). Available pack sizes: 50g, 250g, 5g, 25g, 100g, 10g, 500g, 1kg.