miascite
/ˈmʌɪəskʌɪt/Mineralogy. Now historical
noun
A mineral which is now known to be a mixture of strontianite and calcite.
Origin
Early 19th century; earliest use found in Annals of Philosophy. From Miass, the name of a town on the river Miass in the Urals where the mineral was first obtained + -ite.