Note 217 — TOURMALINE.
William Johnston translation
India produces also the lychnites, the splendour of which is heightened when seen by the light of lamps; and on this account it has been so called by the Greeks. It is of two colours; either a bright purple, or a clear red, and if pure is thoroughly transparent. When heated by the rays of the sun, or by friction, it attracts chaff and shavings of paper. It obstinately resists the art of the engraver.—Solinus, c. lii. p. 59. Traj. 1689, fol.