Catalogue No.
1651
Prism, Optically Worked 1652 - Prism, Optically Worked
Equilateral Two Face Polished, 25x25mmHeight
Equilateral Two Face Polished, 25x25mmHeight
| Nature of Glass | R.I. Appr. |
|---|---|
| a) Borosilicate Crown Glass | 1.51 |
| b) Dense Flint Glass | 1.62 |
| c) Extra Dense Flint Glass | 1.65 |
| d) Double Extra Dense Flint | 1.71–1.74 |