Ratna Pariksha is an ancient science on testing gemstones. It was used by the Kosadhyaksha (Superintendent of Treasury) and mentioned in Kautilya's Arthashastra in order to control the trade of pearl, diamonds and all the other important gems in antiquity. It classifies gemstones into Maha-Ratna and Upa-ratna (lit. Great Gems and Second Class Gems).
Ratna Pariksha is mentioned in Kautilya's Arthashastra (323-299 B.C.). Vatsayana, the author of the Kamasutra also mentions rupa-ratna-pariksha.[1] The method was also studied by princes in Karnataka during the medieval period.[2]
The author of this treatise is very commonly known to be one Buddha Bhatt. There is also mention of another author in the medieval period, Thakkar Pheru, who is again credited with having worked on this subject. There's a mention of one Vaidyaraj Shri Radha Krisha Navetia who uses Ratna Pariksha for preparing a type of alcohol meant in the use of gem refining.