in the method for silica and magnesium oxide , the sample is fused with sodium carbonate and the cooled melt is dissolved with perchloric acid in such a manner that it floats free from the crucible ( in previous schemes for the analysis of talc there are frequently mechanical losses due to the difficulty of removing the magnesium silicate melt from the crucible ) .
C0024477
magnesium oxide
C0024467
magnesium