phen·a·cite 
(fĕnə-sīt′) or phen·a·kite (-kīt′)
(fĕnə-sīt′) or phen·a·kite (-kīt′)n.
A natural beryllium silicate, Be2SiO4, occurring as vitreous crystals sometimes used as gems.
[Greek phenāx, phenāk-, impostor + -ITE1.]
- diphase
- diphasic
- diphenhydramine
- diphenoxylate
- diphenyl
- diphenylamine
- diphenylaminechloroarsine
- diphenylhydantoin
- diphenylketone
- diphosgene
- diphosphate
- diphosphoglyceric acid
- diphosphonate
- diphtheria
- diphtherial
- diphtheric
- diphtheritic
- diphthong
- diphthongal
- diphthongization
- diphthongize
- diphycercal
- diphycercy
- diphyletic
- diphyllous