The Diamond Mines of South Africa: Some Account of Their Rise and Development. E-book. Formato PDF Gardner Fred Williams   -  Forgotten Books, 2017  - 

Table of the Distinguishing Characteristics of Gems,' pp. 494 — 499. Optical Properties of the Diamond, Sir David Brewster, Phil. Trans., VIII, 157, 1817. Le Grand Lapidaire, Paris, 1561.