Page:Transactions NZ Institute Volume 15.djvu/493

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Rep. N.Z. Ex., 1865, p. 256) in mammillated and botryoidal forms in amygdaloidal traps and quartzose trachytes, Canterbury; and by Dr. v. Hochstetter (New Zealand, 1863, Eng. ed., p. 96) in the tuffs and conglomerates of Coromandel; agates being mentioned from the same localities and onyx by Dr. v. Haast from the Malvern Hills, Clent Hills, Mt. Somers, etc. Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 494) mentions the occurrence of chalcedony at Moeraki and Otepopo, and agate at Mt. Charles, Otago.

Carnelian is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) in the volcanic rocks at Moeraki and Otepopo, and the porphyritic rocks of Dunedin Harbour; by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) in small geodes in the volcanic rocks of Canterbury; and by Dr. v. Hochstetter (New Zealand, 1863, Eng. ed., p. 96) in the tuffs and conglomerates of Coromandel; and Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 495) describes two inferior specimens from Coromandel.

Plasma.—There are four specimens of this mineral in the collection of the Colonial Museum from Mt. Somers and Gawler Downs. They are of a pale to dark leek green and waxy lustre. It is also mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 266) in the volcanic rocks of Moeraki and Otepopo; and by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256), filling fissures in tertiary quartzose trachyte at Gawler Downs.

Chrysoprase is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) filling cavities in amygdaloidal rocks in Canterbury.

Bloodstone.—There is one inferior specimen in the collection of the Colonial Museum from Clent Hills. It is of a deep green colour with small red spots. Dr. v. Haast mentions its occurrence in small pieces at Snowy Peak and Malvern Hills.

Quartz as Pseudomorphs of Calcite.—There is a specimen of quartz from the Malvern Hills in the collection of the Colonial Museum forming hollow pseudomorphs of rhombohedral crystals of calcite, some of the calcareous crystals being still preserved, and Dr. Haast also mentions the occurrence of a similar mineral at Rakaia Gorge and Clent Hills (Jurors' Rep. N.Z. Ex., 1865, p. 256.)

Quartz Sands.—Heavy deposits of quartz sand in various degrees of purity occur associated with the lower beds of the cretaceo-tertiary formation at Mt. Somers, Limestone Bluff on the Ashburton River, Lake Heron and Waipara, as mentioned by Dr. v. Haast (Geol. Rep., 1870–71, p. 11; and 1873–74, p. 17.)

Tridymite, S̈i.—Small hexagonal plates of tridymite occur in the trachytic rocks of Lyttelton Harbour, and were first recognized by Professor Ulrich in specimens collected by Dr. v. Haast.