CHEMICAL ANALYSIS of Medieval Striated Red Glass[1]
Lawrence Saint was given a piece of medieval red glass containing a bubble which clearly separated the streaky red flashed layer from the clear greenish base glass. Chemical analysis of both the red & green portions of the glass was commissioned by Saint and performed by the chemist Fredrick Wynkoop.
| | Red Portion | Green Portion |
| Silica (sand) | 52.26% | 52.67% |
| Alumina | 3.86% | 3.20% |
| Ferric Oxide (Iron) | .27% | .46% |
| Calcium Oxide (Lime) | 16.16% | 16.55% |
| Magnesium Oxide | 5.31% | 5.43% |
| Titanic Oxide (titanium) | .20% | .20% |
| Manganese Oxide | 1.00% | 1.02% |
| Sodium Oxide (Soda) | .90% | .92% |
| Potassium Oxide (Potash) | 15.27% | 15.06% |
| Phosphoric Anhydride (P2O5) (Bone Ash) | 4.31% | 4.44% |
| Cuprous Oxide (Cu2O) (Copper) | .26% | None |
| Tin | .16% | None |
