CHRYSOLITE. 69 Chemical Characters. Its colours change, but it does hot melt, without ad dition, before the blowpipe; but with borax, it melts iiito a transparent green glass. Constituent Parts. Silica, - 39.00 38.00 38.00 Magnesia, 43.50 39.50 50.50 Iron, - 19.00 19.00 9.50 101.50 96.50 100 Klaproth, Beit. Id. Klap. Vauquelih. b. i. s. 110'. s. 107. Gcognostic Situation. This mineral has hitherto been found only in a loose state: some mineralogists conjecture that it occurs in veins in serpentine, or greenstone; and also in floetz-trap rocks. Geographic Situation. It is brought to Europe from the shores of the Red Sea; and it is alleged to have been found in trap rocks in Bohemia, and the Isle de Bourbon. Uses. This mineral has an agreeable colour and lustre; hence it is employed as a precious stone in different kinds of jewelling, particularly for ring-stones, when it is set in a gold foil. It is the softest of the precious stones; hence jewels of it wear soon, if not carefully worn and kept. It is said that ring-stones of chrysolite, by wearing, soon become dull on the surface, but that the lustre may be restored by immersing them in vegetable oils. E 3 Observations.