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The Collaborative International Dictionary
belonites

Crystallite \Crys"tal*lite\ (kr?s"tal-l?t), n. [See Crystal.] (Min.) A minute mineral form like those common in glassy volcanic rocks and some slags, not having a definite crystalline outline and not referable to any mineral species, but marking the first step in the crystallization process. According to their form crystallites are called trichites, belonites, globulites, etc.

Wiktionary
belonites

n. (plural of belonite English)