Brochantite, Cu4(SO4)(OH)6 is a copper sulphate hydroxide mineral which forms in the oxidising zones of copper deposits. Crystals may be either prismatic or acicular. In this brecciated specimen there are tiny, prismatic crystals in a vhug, and more massive deposits as infills between the various components. The specimen was collected from the Great Orme copper mine, near Llandudno, North Wales.