TRIPOLI

Dictionary of Science, Literature and Art · 1854 · p. 33

A mineral used for polishing, originally from Tripoli in Barbary. It occurs in friable earthy in; dull clay colour. Its e ential components arc silica, alumina, and oxide of iron; but the varieties of tripoli appear to vary extremely in composition. Ehrenberg has found the different tripolis to be aggregates of silicified animal cules. [s. 1286]