From: Potash-lime-silica glass: protection from weathering
SiO2
K2O
CaO
MgO
Na2O
Al2O3
P2O5
Glass M1
48.00 (53.16)
25.50 (18.01)
15.00 (17.80)
3.00 (4.95)
3.00 (3.22)
1.50 (0.98)
4.00 (1.88)
Glass M3
60.00 (62.27)
15.00 (9.93)
25.00 (27.80)
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