Chrysocolla over Quartz

From Tentadora Mine, Payhuano, Huancano District.

The quartz crystal with defined faces and classic pyramidal termination has been completely coated with two generations of chrysocolla. The first coat is only partially visible on three faces. It is relatively smooth and presumably quite thin, but under magnification is shown to have minute “bubbles” of translucent material. The second generation, covering most of the sides and termination, consists of larger bubbles up to 3 or 4 mm across. The colour is predominantly bright turquoise, though small sections have a greener hue, which is probably malachite. There is also a fair amount of unknown black material coating the back. No part of the underlying quartz is visible except the base of the crystal where it has been severed from its matrix.