Element	TPU-1-S		TPU-2-S			TPU-3-S		TPU-4-S		TPU-5-S
Element	wt.%^a	at. %^b		wt.%	at.%	wt.%	at.%	wt.%	at.%	wt.%	at.%
C K	60.63	72.55	63.59		74.13	64.93	75.37	66.34	76.14	65.55	75.88
O K	18.89	16.97	20.50		17.94	19.27	16.79	19.79	17.05	21.21	18.15
Si K	20.48	10.48	15.90		7.93	15.8	7.84	13.88	6.81	12.24	5.97