perimorph

per·i·morph

P0193400 (pĕr′ə-môrf′)n. A mineral that encloses a different mineral.
per′i·mor′phic, per′i·mor′phous adj.per′i·mor′phism n.

perimorph

(ˈpɛrɪˌmɔːf) n (Minerals) a mineral that encloses another mineral of a different type ˌperiˈmorphic, ˌperiˈmorphous adj ˌperiˈmorˌphism n