ellestadite
noun
el·le·stad·ite
ˈeləˌstaˌdīt
plural -s
: a variety of apatite Ca5(F,Cl,OH)[(P,Si,S,C)O4]3 containing silicon, carbon, and sulfur replacing some of the phosphorus
Word History
Etymology
Reuben B. Ellestad, born 1900 American chemist + English -ite