Search Mineralpedia – A Mineral Photo Database and Identification Guide
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
Named in honor of William Edmond Logan, the first Director of the Canadian Geological Survey as the type locality for this mineral is found at the Francon quarry in Montréal, Québec, Canada. Weloganite can be found only in Canada where it occurs with and in alkali intrusive rocks, and at a locality in South Africa. Weloganite is pyroelectric, meaning it generates a temporary charge when heated, and it also has a blue triboluminescence, or light that is generated when broken due to the breaking of the chemical bonds.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/weloganite.pdf