apophyllite

[ uh-pof-uh-lahyt, ap-uh-fil-ahyt ]
/ əˈpɒf əˌlaɪt, ˌæp əˈfɪl aɪt /

noun

a hydrous potassium and calcium silicate mineral occurring in white crystals.

Origin of apophyllite

First recorded in 1800–10; apo- + -phyll + -ite1

Example sentences from the Web for apophyllite

British Dictionary definitions for apophyllite

apophyllite
/ (əˈpɒfɪˌlaɪt, ˌæpəˈfɪlaɪt) /

noun

a white, colourless, pink, or green mineral consisting of a hydrated silicate of calcium, potassium, and fluorine in tetragonal crystalline form. It occurs in cracks in volcanic rocks. Formula: KCa 4 (Si 4 O 10) 2 (OH 1 F).8H 2 O

Word Origin for apophyllite

C19: from French, from apo- + Greek phullon leaf + -ite 1; referring to its tendency to exfoliate