burr-stonen.
/ˈbəːstəʊn/ A siliceous rock of coarse cellular texture, found chiefly in France and North America, and used for millstones; a piece of this rock.
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the world > the earth > structure of the earth > constituent materials > rock > metamorphic rock > [noun] > burr
burr-stone1690
burr1721
1690 London Gaz. No. 2538/4 Her Loading, consisting of about 750 Burr Stones.
1708 London Gaz. 4501/4 A Pink..with her Cargo, consisting in Burstone, Lime, and Glasses for Windows.
1821 Edinb. Philos. Jrnl. 4 246 Particular account of the recently discovered Buhrstone.
1840 W. Humble Dict. Geol. (1843) 35 The substance of burrh-stone, or mill-stone, when unmixed is pure silex.
1850 C. Lyell 2nd Visit U.S. (ed. 2) II. 9 This burr-stone..constitutes one of the members of the Eocene group.
This entry has not yet been fully updated (first published 1888; most recently modified version published online December 2020).
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