Mineralpedia Details for Weddellite
Weddellite
Named for the first discovered occurrence in the Weddell Sea of Antarctica. This authigenic mineral is a constituent of bottom muds, peat sediments, calcareous lake sediments, and may be formed as part of a reaction of lichen-produced oxalic acid and calcite. Additionally, it can be formed from bat guano and is a known component of human kidney and bladder stones. Weddellite can be found in few, but widespread localities. Weddellite will desiccate to whewellite upon atmospheric exposure.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/weddellite.pdf
- Formula
- CaC2O4·2H2O
- Crystal System
- Tetragonal
- Cleavage
- Good, None, None
- Luster
- Vitreous (Glassy)
- Color
- colorless, tan, white, yellowish brown, brown
- Streak
- white
- Class
- Tetragonal - Dipyramidal
- Hardness
- 4
- WebMineral
- View Weddellite
- Mindat
- View Weddellite
Weddellite from near Biggs, Wasco Co., Oregon, United States
As long creamy tan or brown, flattened or platy or fibrous looking crystals to 4mm in pocket. Often found as kidney stones along with whitlockite, apatite and whewellite.
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