Min. [mod. ad. Gr. ἀλλοφανής appearing otherwise, f. ἀλλος other + φαίνειv to show, appear.] A mineral classed by Dana as the first of his Sub-silicates; a hydrated silicate of alumina, with color sky-blue, green, brown, or yellow, which it loses under the blowpipe; whence the name.
1843. Humble, Dict. Geol., Allophane … gelatinizes in acids.
1875. Ure, Dict. Arts, I. 90. Allophanes have been found containing from 14 to 19 per cent. of oxide of copper, which gives them a green colour.
