Of other lead minerals we may mention the basic sulphate lanarkite, PbO PbSO 4; leadhillite, PbSO 4.3PbCO 3; the basic chlorides matlockite, PbO PbC12j and mendipite, PbC1 2.2PbO; the chloro-phosphate pyromorphite, PbC12.3Pb3(P04)2, the chloro-arsenate mimetesite, PbC12.3Pb3(As04)2; the molybdate wulfenite, PbMoO 4; the chromate crocoite or crocoisite, PbCrO 4; the tungstate stolzite, PbW04.
Mendipite and matlockite are mineral oxychlorides.
Chlorine is never found in nature in the uncombined condition, but in combination with the alkali metals it occurs widely distributed in the form of rock-salt (sodium chloride); as sylvine and carnallite, at Stassfiirt; and to a smaller extent in various other minerals such as matlockite and horn-mercury.