burstone

or buhr·stone, burr·stone

[bur-stohn]

noun

any of various siliceous rocks used for millstones.

a millstone of such material.

Origin of burstone

bur(r)⁴ + stone

Also called buhr, burr.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for burstone

Historical Examples of burstone

With the march of improvement, burstone mills went into the discard.
All About Coffee
William H. Ukers
Rynd, rind, n. in a burstone mill, the iron which supports the upper stone.
Chambers's Twentieth Century Dictionary (part 3 of 4: N-R)
Various

British Dictionary definitions for burstone

burstone

noun

a variant spelling of buhrstone

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012