conchoidal


Also found in: Dictionary, Medical, Wikipedia.

conchoidal

[käŋ′kȯid·əl]
(geology)
Having a smoothly curved surface; used especially to describe the fracture surface of a mineral or rock.
References in periodicals archive ?
Despite the fact that prisms of chamids show no evidence of ultrastructure, with fractures appearing conchoidal rather than revealing nanometric units or folios, there is an interesting similarity in their overall interdigitating form with ultrastructure reported for some of the pterioid prisms.
These findings challenge previous ideas about the minimum level of cognitive and morphological complexity required to produce numerous conchoidal flakes," he said.
Por outro lado, o arenito silicificado de fratura conchoidal se encontra disponivel de maneira local dentro dos intersticios dos derramamentos basalticos por toda a provincia de Misiones (Remesal e Chavez 2014), inclusive na area da cidade de Corpus (INSUGEO 2007).
Silcrete may be distinguished from other siliceous rocks by its lustrous conchoidal fracture; it is so strongly cemented that it fractures evenly through grains and matrix, whereas many quartzites fracture around the grains.
There is no discernible cleavage, and the fracture is conchoidal.
Methods typically employed by igneous petrologists and gemologists to identify glass include the observance of conchoidal fracture, determination of hardness, reaction to a hotpoint, microscopy, and spectroscopy (Gemological Institute of America [GIA] 1996; GIA 1998; Hatch et al.
Along with the carbon, broken and irregular fragments of glass shards exhibiting uneven to conchoidal fractures have been noticed in the limestone samples (Fig.
1) contained zircons with varying morphologies, including colorless to brown anhedral fragments with conchoidal fractures and colorless to light brown prisms with aspect ratios of 2.
Medium hard, very pale brown fabric (5YR 7/6) with hackly to conchoidal break, reddish yellow (5YR 7/6) flashes outside; abundant, medium, white to orange, glassy, subrounded to rounded, tabular to spherical inclusions.
10YR4/4 moist: apedal with conchoidal partings around weathered-stone cores (10Y4/1); weathered basalt rock fragments more common with depth; giving way to basalt at depth (obscured but evident on north face of cutting); field pH 7 Location: Mackenzie's Waterholes Creek; north side of railway cutting Site: Gently convex, broad flat spur with local relief <20 m Classification of the silty mantle: Red Podzolic (Stacc et al.
It is generally slate-colored, with white specks, becoming a uniform white where exposed to the light and air, and it breaks with a conchoidal fracture, producing a ragged cutting edge.