Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/38

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26
Mr. William Phillips's Description

and about six fathoms in length; being disposed in bunches, the largest and richest of which were about fifteen feet in length, by as many in depth.

In this lode, the red oxyd of copper was accompanied occasionally by vitreous copper ore, black oxyd of copper, arseniate of copper, arsenical pyrites, quartz, and fluate of lime. Native copper also occurred in considerable quantities, generally in contact with the red oxyd, and more or less intermingled with it. It was sometimes remarkably brilliant, and occasionally occurred regularly crystallized. There were however considerable masses of the red oxyd unaccompanied by any of the above substances, hollow within, and presenting, on being broken, perfect and varied crystallizations. From the depth of fifty-six fathoms, the search for this mineral was continued for forty fathoms lower, with but little success; bunches of a few tons in weight, and smaller quantities were occasionally discovered, but these became less frequent; so that, at ninety-six fathoms under the adit, the further working of this lode was abandoned. At this depth one part of the vein consisted only of gossan, and was six feet in width, forty fathoms from which it narrowed to three feet, and was there composed of yellow copper ore and quartz.

Further east than the principal body of the red oxyd of copper, and at different depths in the Muttrell Lode; that is, nearer the junction of it with the Great Gossan Lode, were found the interesting varieties of the arseniate of copper, and occasionally that substance which in the paper before alluded to has been described by the Count de Bournon, and by him called Cupreous Arseniate of Iron. These substances were also found in considerable abundance at the line of junction of the two lodes, and in its immediate neighbourhood eastward, at various depths, but with scarcely a trace of the red oxyd of copper until the depth of fifty-six fathoms, at which