CER1TE. 569 It is brittle. ' Specific gravity 4.OSS, Cronstedt. 4.660, Klaproth. 4.6ly and 4.4S9, Ilisinger and Berzelius. Chemical Characters. It is infusible before the blowpipe ; but when pulver ised and heated, its colour changes from grey to yellow. ' Constituent Parts. Oxide of Cerium, Silica, Oxide of Iron, Lime, Water, 9S.75 100 Klaproth, Beit. Vauquelin in Annal. b. iv. s. 147. d. Mus. t. v. p. 412. Gcognostic and Geographic Situations. It occurs in a bed of copper-pyrites, along with bis- muth-glance, or sulphuretted bismuth, molybdq/ta, wol fram ? hornblende, actynolite, and mica. The bed is si tuated in gneiss near Riddarhytta in Westmannland in Sweden. Observations. The peculiar metal which characterises this order, was first detected by Ilisinger and Berzelius, who bestowed °n it the name Cerium, from the planet Ceres, discovered ,J 7 Piu2zi. 54.50 67 34.50 17 3.50 2 1.25 2 5.00 and Carbonic Acid, 12 2. Allanite.