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A dense, homogeneous rock with constituents so fine that they cannot be seen by the naked eye.

[From Greek aphanēs, unseen : a-, not; see a-1 + phainesthai, phan-, to appear, passive of phainein, to show; see phenomenon.]

aph′a·nit′ic (-nĭt′ĭk) adj.


of or resembling aphanite
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Adj.1.aphanitic - of or relating to aphanite
References in periodicals archive ?
062 mm were recorded as "labile" (L) according to the criteria of Dickinson (1970), and were usually aphanitic fragments of phyllites, slates and schists.
5-foot thick aphanitic layer of calcarenitic limestone, commonly marly and fossiliferous; (2) a 233-foot thick aphanitic limestone; and (3) a 110.
examine the aphanitic buildup from the onset of the Mulde Event (Homerian, middle Silurian) at Whitman's Hill (UK) and thus open up discussion on the significance of microbial fabrics.
Meanwhile, analyses of this type should be restricted to aphanitic (homogenous and fine-grained) materials.
The texture of the rock is porphyritic aphanitic with phenocrysts surrounded by microcrystalline matrix made of microlites of euhedral plagioclase grains.
Andesite is an aphanitic and extrusive igneous rock composed of the Na-rich plagioclase, pyroxene and amphibole.
Basaltic to andesitic rocks of the East Bay Hills Group are typically aphanitic and massive, with slight to moderate porphyritic textures.
Microstructure of aphanitic clay is less sericitizated and is obviously orientational.
aphanitic igneous and silicified rock), and low quality raw material (e.
Two small exposures of atypical, grayish green, aphanitic skarn that host splotches of pink rhodonite, massive epidote and an unknown brown mineral have been exposed at the lowest peripheries of both the middle and lower workings (see under Rhodonite).
At San Diego, silica flooding and hairline quartz veinlets obscure breccated aphanitic rock in four outcrops that protrude through shallow soil and elluvial cover over a 20 x 30 meter area.