Opalescence and Glass Ceramics

In general, a small degree of devitrification (crystallisation) (-5%) leads to opalescence, while large amounts ( 85%) can produce glass-ceramic materials with their well-known properties of high strength and high thermal shock resistance. 

Recent applications of P205-containing glass ceramics are in the field of biomaterials (Section 12.13). Biomedical applications are important [28] (Section 12.13). 

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