collophane

[ kol-uh-feyn ]
/ ˈkɒl əˌfeɪn /

noun Mineralogy.

a massive, cryptocrystalline variety of apatite that is the principal component of phosphate rock and fossil bone.
Also col·loph·a·nite [kuh-lof-uh-nahyt, kol-uh-fuh-] /kəˈlɒf əˌnaɪt, ˈkɒl ə fə-/.

Origin of collophane

1915–20; < German Kollophan, equivalent to Greek koll(a) glue + -o- -o- + -phan -phane