allomerous, a.
(æˈlɒmərəs)
[f. as prec. + -ous.]
Liable to variation in constituent elements or as to the proportion in which these are present, without change in crystalline form.
Allomerous is (to some extent) the correlative of isomorphous; hornblende, tremolite, and edenite are isomorphous minerals, being varieties of the allomerous amphibole (see prec.); but distinct minerals are also isomorphous, as gold, platinum, and zinc; phosphate of lime (apatite) and phosphate of lead (pyromorphite); sesquioxide of iron and sesquioxide of manganese; which are not varieties of a single allomerous substance, though, as in the case of the two last mentioned, they may appear as isomorphous constituents of an allomerous compound mineral like amphibole or pyroxene.