Phosphate

	FROM	TO
Refractive Index nD	1.523	1.530
Refractive Index nF	1.534	1.546
Refractive Index nC	1.520	1.526
Abbe Number	64	65.5
Density (g/cc)	2.60	2.75
Termal Expansion	82	94
Knoop Hardness (kg/mm2)	430	480