CERUSSITE MALACHITE PYROMORPHITE
A very aesthetic specimen of Cerussite Malachite Pyromorphite from the Top End. Well formed Pyromorphite and interesting Cerussite crystals on Malachite. The Malachite is chatoyant and in botryoidal form with some velvet covering. A super piece from a great Aussie location. Amazing to look at under magnification. From one collector to another.
5.5cm x 4.3cm x 2.2cm, 60g.
Browns Deposit, Rum Jungle, NT.
Cerussite is a popular collection mineral. It is famous for its great sparkle, great density and amazing twinned crystals. Cerussite is a minor ore of lead. It has a very high luster due mostly to the lead content. Just as leaded crystal glass sparkles more brilliantly because of its lead content, so too does Cerussite. The lead raises the index or refraction of Cerussite to just over 2.07. Lead is also responsible for its increased specific gravity. Cerussite has one of the highest densities for a transparent mineral. It is over six and a half times as dense as water. Most rocks and minerals average only around three times the density of water.
Copper Carbonate Hydroxide:
Malachite is a green, very common secondary copper mineral with a widely variable habit. Found as crystalline aggregates or crusts, often banded in appearance, like agates. Also formed as botryoidal clusters of radiating crystals, and as mammillary aggregates. Named from Pliny the Elder as molochitus after the Greek mallows in allusion to the green colour of the leaves. Known in the new spelling, malachites, at least by 1661. Malachite is a green and common secondary copper mineral with widely variable habit. Frequently found as a pseudomorph after Azurite crystals, which are generally more tabular in shape.
A member of the Apatite family. Pyromorphite shares the same structure with apatite and therefore crystals of the two will have similar shapes. Pyromorphite also forms a chemical series with two other minerals; Mimetite (Pb5(AsO4)3Cl) and Vanadinite (Pb5(VO4)3Cl). This series is a little different than most chemical series which involve substitution of cations such as calcium for magnesium. Instead, this series substitutes its basic chemical units the anion groups; phosphate (PO4), arsenate (AsO4) and Vanadate (VO4). Green Mimetite or yellow Pyromorphite can make identification between the two difficult. Usually Pyromorphite is green and Mimetite is yellow. Vanadinite is usually red. It has a unique crystal habit of stacked barrel shaped crystals. They branch out in a way that is reminiscent of some branching cactus varieties. So please check out carefully this specimen available.