It is well known to mixers that colored glass is derived from metallic oxides. To obtain the proper color depends on the purity and strength of the metallic oxides. The following receipts have with success been used:—
ALABASTER.
| To | 500 | lbs. | of batch add |
| 30 | " | phosphate of soda, | |
| 10 | " | allumine,—i.e. calcined alum, | |
| 3 | " | calcined magnesia. | |
BLACK.
| To | 1400 | lbs. | of batch add |
| 180 | " | manganese, | |
| 100 | " | calcined iron scales, made fine, | |
| 20 | " | powdered charcoal, | |
| 10 | " | arsenic. | |
CANARY.
| To | 100 | lbs. | of batch add |
| 8 | ounces | best oxide of uranium, | |
| 1 | dr. | oxide of copper. | |
The common colors of purple, blue, emerald, or green, are too well known to require to be repeated here.
The following receipt for crystal glass is on the European standard, viz.:—
| 1200 | lbs. | silex, |
| 800 | " | red lead, |
| 440 | " | pearlash, |
| 50 | " | nitre, |
| 10 | " | phosphate of lime, |
| 10 | oz. | white oxide of antimony, |
| 24 | " | manganese, |
| 32 | " | arsenic, |
| 20 | " | borax. |