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Formula: PbAl2(CO3)2(OH)4.H2O
Hydrated carbonate containing hydroxyl, dresserite group
Crystal System: Orthorhombic
Specific gravity: 3.1 to 3.55 measured, 3.716 calculated
Hardness: 2
Streak: White
Colour: White to colourless to very pale blue
Solubility: Soluble in acids with effervescence
Environments
Dundasite is an uncommon secondary
mineral found in the oxidation zone of lead deposits. Associated minerals include
cerussite, plattnerite,
azurite, malachite,
pyromorphite, mimetite,
beudantite, duftite,
crocoite, gibbsite,
allophane, galena and
limonite
(HOM, Mindat).
Localities
At the Hercules Mine, Williamsford, Rosebery district, West Coast municipality, Tasmania, Australia, dundasite
occurs with cerussite and gibbsite
(Dana).
At the type locality, the Adelaide mine, Dundas mineral field, Zeehan District, West Coast municipality, Tasmania,
Australia, dundasite occurs as aggregates of white to pale blue crystals to 1 mm in length; it commonly
overgrows crocoite and may in turn be overgrown by cream to white
gibbsite, yellow cerussite or,
less commonly, a later generation of crocoite
(AJM 12.2.81).
At Port Quin Mine, Port Quin, St Minver, Cornwall, England, UK, dundasite is associated with
allophane
(Dana).
At Killhope, Stanhope, County Durham, England, a single specimen has been found with white pearly flakes of
dundasite covering a tiny area on iron-stained cerussite in a small
mass of galena
(JRS 13.63).
At the Mill Close mine, Wensley, South Darley, Derbyshire, England, UK, dundasite is associated with
cerussite, hemimorphite and
greenockite
(Dana).
At Torr Works Quarry (Merehead Quarry), Cranmore, Mendip, Somerset, England, UK, specimens have been found consisting
of calcium-bearing dundasite intergrown with lead-bearing
alumohydrocalcite in cavities in a manganese oxide matrix
(JRS 13.34).
At Trefriw, Conwy, Wales, UK, dundasite is associated with cerussite
and allophane
(Dana).
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