Page:Transactions NZ Institute Volume 15.djvu/480

These are only hydrous shales containing a certain percentage of carbonaceous matter, and are not of any use for the distillation of oil.

Carbonaceous Mineral, Whangarei.—This is described by Captain Hutton (Trans. N.Z. Inst., vol. iii., p. 250) as follows:—"Colour black, with shining resinous lustre; streak and powder, black; very brittle, but does not dirty the fingers. H. about 2. In the flame of a spirit lamp it burns to a white ash without altering its shape, and without giving off any odour or smoke, but it will not burn if taken out of the flame. It appears to be nearly pure carbon without any admixture of bitumen. Dr. Hector gives the following composition for this mineral:—

from which it appears to be a non-caking lignite approaching jet, burning with difficulty, giving but little flame, and a white ash.

Elaterite (Elastic Bitumen), CH₂.—The occurrence of this mineral on the coast of the North Island is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 425) as easily impressed by the nail, and perfectly free from any impurities. Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 491) again mentions its occurrence at Poverty Bay, the following being his description of the specimen:—"The exterior surface is of a brown colour, within it is black, burns with a luminous smoky flame, emitting a bituminous odour; leaves a small quantity of white ash; breaks with conchoidal fracture; very brittle; possesses bituminous odour."

It has only up to the present time been found as pieces on the East Coast of the North Island, and on the Island of Kawau, and may possibly not be a natural product, but lost from some ship.

Petroleum.—The first mention of this mineral oil is by Dr. Hector (Geol. Rep., 1866–67, p. 4), where he describes its mode of occurrence at Taranaki, and he has also (Geol. Rep., 1873–74, p. xviii.) given a description of the oil-springs at Poverty Bay.

Mr. Skey has, in a paper on the mineral oils of New Zealand (Trans. N.Z. Inst., vol. vi., p. 253), given a very good description of their physical characters.

1. Sugar Loaves, Taranaki.—A. very remarkable oil having sp. gr. .960 to .964 at 60° Fahr., dirty green colour by reflected light; opaque, except in thin films, when it has a deep red colour by transmitted light. At 60° Fahr. is quite liquid, and though at lower temperature it has considerable consistency, yet when reduced to 5° Fahr. it does not become solid. Has