Comparative Compostitions
| Egyptian 15th Cent. BC |
Roman 1st Cent. AD |
European 13th Cent. AD |
Syrian 14th Cent. AD |
Modern | |
|---|---|---|---|---|---|
| Silica, SiO2 | 65 | 68 | 53 | 70 | 73 |
| Soda, Na2O | 20 | 16 | 3 | 12 | 16 |
| Potash, K2O | 2 | 0.5 | 17 | 2 | 0.5 |
| Lime, CaO | 4 | 8 | 12 | 10 | 5 |
| Magnesia, MgO | 4 | 0.5 | 7 | 3 | 3 |
| Batch Materials | plant ash quartz |
natron sand |
wood ash sand/quartz |
plant ash sand/quartz |
synthetic components |
Typical compositions of some historical and ancient glasses. The components are given in weight per cent. In addition to those listed the ancient glasses would also have contained up to one per cent iron oxide and up to three per cent aluminium oxide, in addition to any colorants and opacifiers.
Read more about this topic: Forest Glass
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