wall rock

American  

noun

Mining.

1. the rock forming the walls of a vein.

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wall rock British  

noun

1. rock that is immediately adjacent to a mineral vein, fault, or igneous intrusion

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Etymology

Origin of wall rock

An Americanism dating back to 1855–60

Example Sentences

All I could make out was the endless ramp, the wall rock, thick cables bolted to the granite, looping on ahead until they disappeared where the headlights lost themselves in the dark air.

From The Wall Street Journal • Dec. 13, 2013

Association with typical hot-water minerals and hydrothermal alterations of the wall rock are again believed to indicate the origin of the ores through ascending hot solutions from a deep source.

From The Economic Aspect of Geology by Leith, C. K. (Charles Kenneth)

In igneous rock the ore-bearing solutions may have altered the wall rock to a dense mixture of quartz, sericite, and chlorite.

From The Economic Aspect of Geology by Leith, C. K. (Charles Kenneth)

Their principal occurrence is in distinct fissure veins in igneous rocks, with more or less replacement of the wall rock.

From The Economic Aspect of Geology by Leith, C. K. (Charles Kenneth)

The ore fills fissures to some extent, but is mainly a replacement of the wall rock.

From The Economic Aspect of Geology by Leith, C. K. (Charles Kenneth)