Images
Formula: NaAl(CO3)(OH)2
Anhydrous carbonate containing hydroxyl
Crystal System: Orthorhombic
Specific gravity: 2.436 measured, 2.431 calculated
Hardness: 3
Streak: White
Colour: Colourless, white
Solubility: Soluble in acids with effervescence
Environments
Dawsonite is a low temperature hydrothermal carbonate formed from decomposing aluminous silicates.
Localities
At the Francon quarry, Montréal, Québec, Canada, colourless dawsonite crystals occur with dark green
microcrystals of marcasite on a matrix of fluorite
Mindat photo)
Dawsonite from the Francon Quarry -
Image
At McGill University campus, Quebec, Canada, dawsonite is found as coatings on joint surfaces of a
feldspar dyke associated with calcite,
dolomite, pyrite,
galena and manganese oxides.
Dawsonite from the McGill University
Campus - Image
In Solingen, North Rhine-Westphalia, Germany, dawsonite occurs in veins associated with late Tertiary
basalt.
At Santa Fiora, Tuscany, Italy, dawsonite is associated with calcite,
dolomite, pyrite,
fluorite and cinnabar
(Dana).
Dawsonite from Santa Fiora - Image
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