bult·fon·tein·ite \ˌbəlt(ˌ)fän.ˈtāˌnīt, -_fən\noun (-s) Usage: usually capitalized Etymology:Bultfontein, village in Cape Province, Union of So. Africa + English -ite : a mineral Ca2SiO2(OH,F)2 consisting of calcium silicate with hydroxyl or fluoride that is found at Bultfontein, So. Africa