Page:Transactions NZ Institute Volume 15.djvu/512

brown and red, and occurs in considerable quantities at some places. It is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257, and Geol. Rep., 1873–74, p. 9) associated with the quartz porphyries of Mount Somers and Snowy Peak.

Spinel, Ṁg …Al.—The occurrence of rubies with garnet and topaz in the alluvium of Waipori, Otago, is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 416). This mineral is also mentioned from Manawatu, Wellington (Col. Mus. and Lab. Rep., v., p. 18) as rhombic dodecahedrons, and nearly opaque. They were not analyzed, and so are very probably garnets.

Zircon, (symbol characters)r, S̈i.—The occurrence of this mineral is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 417, 438), who says "crystals of zircon were exhibited, in the Museum of the Geological Survey, from Timbril's Gully," and (Trans. N.Z. Inst., vol. ii., p. 371) with platinum and gold in the wash of the south; and by Dr. v. Haast from the western slopes of the Southern Alps (Geol. Rep., 1870–71, p. 24). In the collection of the Colonial Museum there is a specimen of a biotite rock from Doubtful Inlet, Otago, in which there are numerous minute tetragonal prisms with pyramidal ends of a bright red colour, transparent, which are probably zircons.

Topaz, 5 …Al S̈i + (Al F3 + Si F2).—Is mentioned by Dr. Hector at Chatto Creek, Arrow River, and Waipori (Jurors' Rep. N.Z. Ex., 1865, pp. 265, 438); and (p. 416) he says, "in collections from the Otago Goldfields' department were some uncut topazes as large as pigeons' eggs, and of a pure white colour. Several smaller topazes of various colours have lately come into the possession of the Geological Survey of Otago from the neighbourhood of Waipori, where they are found in the alluvium along with rubies, garnets," etc.

Emerald, …Al S̈13 + 3 Ġl S̈i.—Specimens of this mineral have been forwarded from Dusky Sound by Mr. W. Docherty, of which Mr. Skey says:—"This is a somewhat rare mineral collected by Mr. William Docherty, from a vein in the vicinity of Dusky Sound. When tested, it was found to be the mineral beryl, the distinguishing feature of which is the presence therein of the rare metal glucinum (beryllum.) Usually, this is to the extent of 12 to 15 per cent. in specimens of this kind. The mineral is of a full rich green colour, which it owes to the presence of sesquioxide of chrome. It occurs at Dusky Bay, in a pyrrhotiniferous quartz, forming little nests of confusedly crystalline masses having a tendency to assume a tabular form."