Table 1. Elemental Composition of PESHA.

elements	atom %	wt %
O	64.90	54.61
Ca	9.72	20.48
P	5.94	9.68
Mg	0.62	0.79
C	15.99	10.10
Si	1.29	1.90
K	0.66	1.36
Na	0.89	1.07