collophane

American  

[kol-uh-feyn] / ˈkɒl əˌfeɪn /

Also collophanite

noun

Mineralogy.

1. a massive, cryptocrystalline variety of apatite that is the principal component of phosphate rock and fossil bone.

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Etymology

Origin of collophane

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