conchoidal


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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 ?
The glass shards are colourless, irregular to rounded in shape, crystalline in nature and exhibits conchoidal to irregular fractures within them (Fig 8 ).
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.
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.
There is also misunderstanding of the term conchoidal fracture, which is an intrinsic property of some rocks, not a technique of knapping as suggested in some chapters.
The typical clay lithology of the Porters Creek consists of medium to dark gray clay which breaks with a conchoidal fracture.