Type               SG      RI
colorless          2.3     1.47 borosilicate
pale blue          2.35    1.5     "
yellow             2.43    1.498 calcium
blue               2.44    1.515 fused beryl
emerald green      2.49    1.516 fused beryl
colorless          2.87    1.54  light flint
yellow             3.627   1.633 lead(flint)
ruby red           3.69    1.63  lead
jade               3.73    1.63  lead
colorless          3.74    1.635
orange             4.12    1.68  lead
red                4.16    1.683 lead
emerald            4.25    1.70  lead
yellow             4.98    1.77  lead
refractometer glass6.33    1.962 extra dense
                                 lead(flint)