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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
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.aphanitic - of or relating to aphanite
References in periodicals archive ?
Creamy white quartz contains black and grey sulfides with pyrite along the margins, cut by clear aphanitic chalcedony veins.
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.
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.
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.
12m is a dark green, aphanitic to fine grained, weakly to moderately magnetic Trace disseminated chalcopyrite are at 66.