... Standard: Industrial Grade Purity: 46% Appearance: flakesApplication: mgo board production K: less than 0.01 Na: Less than ... theft covers, fireproof doors and Windows, fire prevention board, partition board, the production of artificial marble and so on ... clay, high quality system of fire prevention board, magnesium magnesium packing, decoration board, light wallboard, abrasive, stoves, fireworks guide ...