Alum-shale

Definitions

  • Chambers's Twentieth Century Dictionary
    • ns Alum-shale a slate consisting mainly of clay, iron pyrites, and coaly matter, from which alum is obtained
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Etymology

Chambers's Twentieth Century Dictionary
L. alumen.

Usage

In literature:

When exposed to the atmosphere, these shales yield a small deposit of alum.
"Scientific American Supplement, Vol. XXI., No. 531, March 6, 1886" by Various
Fifty tons of this burnt shale are required to make one ton of alum.
"A Month in Yorkshire" by Walter White
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