Page:Transactions NZ Institute Volume 15.djvu/482

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Ambrite (Retinite).—Dr. v. Hochstetter is the first to mention the occurrence of this mineral in New Zealand (New Zealand, 1863; Eng. ed., p. 79). He describes it as follows:—"Fossil resin imbedded in the coal, sometimes in pieces from the size of a fist to that of a man's head, but usually only in smaller groups. It is transparent, very brittle, and has a conchoidal and quite glossy fracture. Colour changes from a bright yellow to dark brown; is easily ignited, much more so than the kauri gum; burns with a steady fast sooting flame, and developes a bituminous rather than aromatic smell. Mr. Richard Maly found as a mean of three chemical analyses of this fossil resin—

Carbon	76.53	Computed	76.65
Hydrogen	10.58	Computed„	10.38
Oxygen	—	Computed„	12.78
Ash	.19	Computed„	.19
			100.00

yelding the formula C³² H{[sup|26}} O⁴. It shows great indifference to solvents; by friction it becomes electric; H. 2, sp. gr. 1.034 at 12° R. It is sufficiently characterized to deserve a special name, but it comes so near to real amber in composition that it deserves the name of Ambrite."

Dr. Hector also mentions its occurrence (Jurors' Rep. N.Z. Ex., 1865, p. 426) under the name of Retinite, in the brown coals of Hyde, Caversham, Tuapeka, Waitahuna, and Dunstan; and Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 490) again describes samples from Dunstan and the Bay of Islands. It is of common occurrence in the brown coals of New Zealand wherever they occur, being sometimes in moderately large blocks, and at others as dispersed grains.

Mellite, …Al M³ + 18 Ḣ.—A specimen of this mineral was first collected by Captain Hutton from the Thames in 1870, and the specimen is described (Col. Mus. & Lab. Reps., vi., p. 15) as a resinous looking substance, with a splintery fracture. Another specimen was collected by Dr. Hector in 1876 from a cave in Bligh Sound, and is mentioned in the Twelfth Laboratory Report under the number 1913. There is no description and none of the mineral remains.

Non-Metallic Minerals.—Class III.

Sulphur and Selenium.

Sulphur, S.—Considerable quantities of this valuable mineral occur on White Island, where it is deposited from numerous geysers and an enormous boiling spring near the centre of the island (Hector, Jurors' Rep. N.Z. Ex., 1865, pp. 34, 425), and it occurs in smaller quantities on various other islands in the Bay of Plenty. It is also deposited from fumaroles at the Rotomahana hot lakes and Taupo, and in several other localities where hot