Page:Transactions NZ Institute Volume 15.djvu/502
4.5; sp. gr. 2.592. Is completely decomposed by hydrochloric acid. In blowpipe flame infusible, turns faint buff colour, no distinct soda reaction, but slight reaction of manganese with the proper fluxes."
Analysis.
| 1. | 2. | 3. | |||
| Silica | 40.20 | 41.20 | 45.91 | ||
| Protoxide of iron | 12.10 | 12.10 | 1.67 | ||
| Alumina | traces | traces | 5.63 | ||
| Manganese | traces„ | traces„ | traces | ||
| Chromium | traces„ | traces„ | traces„ | ||
| Magnesia | 33.20 | 34.02 | 35.07 | ||
| Water of constitution | 12.70 | 12.74 | 12.67 | ||
| 98.20 | 100.06 | 100.95 |
This is alluded to by Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 497) as marmolite.
There is also a specimen in the collection of the Colonial Museum, from Jackson's Bay, which is of a grass-green colour, translucent and laminated.
Antigorite.—The occurrence of this mineral at the Dun Mountain is mentioned by the late Mr. E. H. Davis (Geol. Rep., 1870–71, p. 112).
Hectorite occurs at the Dun Mountain, Nelson (for description see below, Art. xlviii.).
Picrolite, a coarsely fibrous variety, of dark dirty green colour, occurs at the Dun Mountain.
Chrysotile occurs as thin veins of a silky texture and pale green colour traversing the dark green serpentine of the Dun Mountain.
Picrosmine, 2 Ṁg S̈i + Ḣ.—A massive sectile variety of this mineral, of a greenish-grey colour, occurs associated with chromite at the Dun Mountain; it is also found as a network of veins, in which crystals of bronzite occur, in the same district.
Schiller Spar, Ṁg (Ḟe, Ċa), S̈i (, , ) + Ḣ.—The occurrence of this mineral with pyrites on the West Coast is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 266).
Chlorite, 2 Ṙ S̈i + Ṙ2 + 3 Ḣ, occurs as a constituent of the chlorite schists, which are found in many localities between Otago and Nelson on the West Coast side of the South Island. It is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) in the schist of the West Coast, and also as an amorphous form in the vesicular basalts of Otago Heads and elsewhere; by Dr. v. Haast in laminæ in the metamorphic schists of the West Coast, (Jurors' Rep. N.Z. Ex., 1865, p. 257); by Mr. Skey, at Tararu Creek, Thames (Geol. Rep., 1870–71, p. 88); by myself in chlorite schists at the Fox Glacier, Westland (Geol. Rep., 1874–76, p. 73); and by Professor Liversidge, from Deep Creek, Kakapo Lake (Trans. N.Z. Inst., vol. x., p. 497).