microsommite
/mʌɪkrə(ʊ)ˈsɒmʌɪt/Mineralogy
noun
A trigonal aluminosilicate of sodium, calcium, and potassium which occurs as colourless crystals in volcanic rocks.
Origin
Late 19th century; earliest use found in The Encyclopedic Dictionary. From Italian microsommite from micro- + Somma, name of one of the volcanic peaks of Vesuvius + -ite.