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358 SILICATES. readily into a clear glass slightly coloured by iron. With salt of phosphorus the silica intumesces so that the bead cannot take a globular form. In hydrochloric acid is partly decom posed and gelatinizes. 2RSi + ZrSi, where It denotes soda, lime, protoxides of iron and manganese. Analyses a by Stromeyer, corrected by Rammelsberg, b by Rammelsberg:— a b Silica 49-92 Zirconia . 10-89 16-88 Protoxide of iron . . . 6-16 097 Protoxide of manganese 231 1-16 Lime . 10-14 11-11 Soda j 13-92 12'28 Potash 0-65 Chlorine 1-19 Loss by ignition .... 1-80 0-37 Rammelsberg supposes that in analysis a the silica contained some zirconica. According to Svanberg, the zirconia obtained from eudialyte contains a new oxide, resembling, in some of its properties, the substance which went by the name of yttria previous to its separation into yttria and the oxides of erbium and terbium, but does not perfectly resemble either of them. In attached crystals; massive, granular, disseminated. Is found at Kangerdluarsuk in West Greenland with soda- lite, arfvedsonite and felspar. 201. WOIILERITE.—Wohlerite ; Dufrenoy. Wohlerit; Hausmann, Haidinger. Traces of cleavage. Fracture conchoidal...splintery. Trans lucent more or less. Lustre vitreous, on surfaces of frac ture resinous. Yellow, brown, grey. Streak yellowish-whito. it = 6'6. o = 3'4I. Before the blowpipe in a strong heat melts quietly into a yellowish glass. Imparts the colours of iron and manganese to borax and salt of phosphorus. Is decomposed by warm concen trated hydrochloric acid, leaving a residue of silica and pelopic acid. Analysis by Scheerer:— Silica 30-02 Pelopic acid ..... i i’47 Zirconia 16-17
