Cerussite

Cerussite (also known as lead carbonate or white lead ore) is a <a href="/facts/Mineral/LkUFbNmv">mineral</a> consisting of <a href="/facts/Lead_carbonate/KXw6ux0H">lead carbonate</a> with the chemical formula PbCO3, and is an important <a href="/facts/Ore/kgc9DssX">ore</a> of lead. The name is from the <a href="/facts/Latin/pM3Kge85">Latin</a> cerussa, <a href="/facts/White_lead/MoKMLsH9">white lead</a>. Cerussa nativa was mentioned by <a href="/facts/Conrad_Gessner/m4DqHYJx">Conrad Gessner</a> in 1565, and in 1832 <a href="/facts/Fran%25C3%25A7ois_Sulpice_Beudant/WEzY5tvY">F. S. Beudant</a> applied the name céruse to the mineral, whilst the present form, cerussite, is due to <a href="/facts/W._Haidinger/pbeHUQVB">W. Haidinger</a> (1845). Miners' names in early use were lead-spar and white-lead-ore.
Cerussite <a href="/facts/Crystal/e2R2mk3E">crystallizes</a> in the <a href="/facts/Orthorhombic_crystal_system/3zo4F8P0">orthorhombic crystal system</a> and is isomorphous with <a href="/facts/Aragonite/QGcD3SLs">aragonite</a>. Like aragonite it is very frequently <a href="/facts/Crystal_twinning/7xU6CKfR">twinned</a>, the compound crystals being pseudo-hexagonal in form. Three crystals are usually twinned together on two faces of the prism, producing six-rayed stellate groups with the individual crystals intercrossing at angles of nearly 60°. Crystals are of frequent occurrence and they usually have very bright and smooth faces. The mineral also occurs in compact granular masses, and sometimes in fibrous forms. The mineral is usually colorless or white, sometimes grey or greenish in tint and varies from transparent to translucent with an adamantine lustre. It is very brittle, and has a <a href="/facts/Conchoidal_fracture/2tg82TPw">conchoidal fracture</a>. It has a <a href="/facts/Mohs_hardness/wXBMcVIm">Mohs hardness</a> of 3 to 3.75 and a <a href="/facts/Specific_gravity/ySquGd2x">specific gravity</a> of 6.5. A variety containing 7% of zinc carbonate, replacing lead carbonate, is known as iglesiasite, from Iglesias in <a href="/facts/Sardinia/7GGJNHCx">Sardinia</a>, where it is found.
The mineral may be readily recognized by its characteristic twinning, in conjunction with the adamantine lustre and high specific gravity. It dissolves with effervescence in dilute <a href="/facts/Nitric_acid/UDbwGp6s">nitric acid</a>. A <a href="/facts/Blowpipe_(tool)/SwzJ9bbV">blowpipe test</a> will cause it to fuse very readily, and gives indications for lead.
Finely crystallized specimens have been obtained from the <a href="/facts/Lahnstein/Gl3EqeFa">Friedrichssegen</a> mine in <a href="/facts/Lahnstein/Gl3EqeFa">Lahnstein</a> in <a href="/facts/Rhineland-Palatinate/Ny2D4pbe">Rhineland-Palatinate</a>, <a href="/facts/Johanngeorgenstadt/blB13Ipu">Johanngeorgenstadt</a> in <a href="/facts/Saxony/PrKscwCP">Saxony</a>, <a href="/facts/St%25C5%2599%25C3%25ADbro/L8Kujqr8">Stříbro</a> in the <a href="/facts/Czech_Republic/vJYLD66Q">Czech Republic</a>, <a href="/facts/Phoenixville/uMMQmHtm">Phoenixville</a> in <a href="/facts/Pennsylvania/HGqC5bBm">Pennsylvania</a>, <a href="/facts/Broken_Hill%2c_New_South_Wales/GA4urFEC">Broken Hill in New South Wales</a>, and several other localities. Delicate <a href="/facts/Acicular_(crystal_habit)/PGMnp4TX">acicular</a> crystals of considerable length were found long ago in the Pentire Glaze mine near <a href="/facts/St_Minver/30XFNGgr">St Minver</a> in <a href="/facts/Cornwall/9A3TftFP">Cornwall</a>. Cerussite is often found in considerable quantities, and has a lead content of up to 77.5%.
Lead(II) carbonate is practically insoluble in neutral water (solubility product [Pb2+][CO32−] ≈ 1.5×10−13 at 25 °C), but will dissolve in dilute acids.

Cerussite open-in-new

Cerussite