Search Mineralpedia – A Mineral Photo Database and Identification Guide
Phyllosilicate - Monoclinic - Not a Mica group member. But is micaceous. A member of the Montmorillonite-Vrmiculate group with 2:1 layering, meaning there are two (T) tetrahedral layers with an (M) octahedral layer in between. There is no (I) interlayer and the 2:1 layers are instead held together by weak Van der Waals bonds.
Requires Biotite, Chlorite, Hornbelnd and Serpentines to form. Vermiculite contains so much water it will exfoliate when burned.
William E. Ver Planck, a geologist for the California Division of Mines and Geology in California, USA has the mineral Verplanckite named for him. It is found in metamorphic canbornite-quartz rocks as thin layers in only one locality in the world, its type locality, at the Esquire No. 7 claim in California.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/verplanckite.pdf
Named for the locality of its discovery at Mount Vesuvius in Italy. Vesuvianite is formed within skarns that formed as a result of regional or contact metamporphism of limestones, and in gabbros containing garnet, mafic and ultramafic rocks as well as serpentinites. Vesuvianite is found in over 1,000 localities worldwide. Sometimes called idocrase.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/vesuvianite.pdf