[Pramāṇa](https://indike.org/pramana/) › [Studies](https://indike.org/pramana/ins) › [Science, technology and education](https://indike.org/pramana/ins.science) › [A History of Hindu Chemistry from the Earliest Times to the Middle of the Sixteenth Century A.D.](https://indike.org/pramana/ins.science.ray-1902) › v2.c32.s16.31 # A History of Hindu Chemistry from the Earliest Times to the Middle of the Sixteenth Century A.D. v2.c32.s16.31 A History of Hindu Chemistry from the Earliest Times to the Middle of the Sixteenth Century A.D. v2.c32.s16.31 - **Language:** English ### [v2.c32.s16.31](https://indike.org/pramana/ins.science.ray-1902.v2.c32.s16.31) black, red or copper-tinted.\* Stones which are translucent, opaque and of dull colour are inferior in quality. In the case of diamond special stress is laid on its displaying the colours of the rainbow \[due to its high dispersive power\]. Some gems have only one shade of colour (एकच्छाय), others again two (द्विच्छाय).† - [Previous: v2.c32.s16.30](https://indike.org/pramana/ins.science.ray-1902.v2.c32.s16.30) - [Next: v2.c32.s16.32](https://indike.org/pramana/ins.science.ray-1902.v2.c32.s16.32) - [Up: v2.c32.s16](https://indike.org/pramana/ins.science.ray-1902.v2.c32.s16) --- Source: [https://indike.org/pramana/ins.science.ray-1902.v2.c32.s16.31](https://indike.org/pramana/ins.science.ray-1902.v2.c32.s16.31) · Pramāṇa