clinkstone
noun
a variety of phonolite that makes a metallic sound when struck
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Examples from the Web for clinkstone
Historical Examples of clinkstone
A fissile texture is occasionally assumed by clinkstone and other trap rocks, so that they have been used for roofing houses.
A Manual of Elementary GeologyCharles Lyell.
(c.) Phonolite (Clinkstone) is a trachytic rock, composed essentially of sanidine, nepheline, and augite or hornblende.
Volcanoes: Past and PresentEdward Hull
Some varieties are slaty, and are frequently mistaken for clinkstone, which they closely resemble.
GeologyJames Geikie