burr-stone
(ˈbɜːstəʊn)
Also buhr-, burrh-, bur-.
[f. burr n.5 + stone.]
A siliceous rock of coarse cellular texture, found chiefly in France and N. America, and used for millstones; a piece of this rock.
| 1690 Lond. Gaz. No. 2538/4 Her Loading, consisting of about 750 Burr Stones. 1708 Ibid. 4501/4 A Pink..with her Cargo, consisting in Burstone, Lime, and Glasses for Windows. 1821 Edin. Philos. Jrnl. IV. 246 Particular account of the recently discovered Buhrstone. 1840 W. Humble Dict. Geol. & Min. (1843) 35 The substance of burrh-stone, or mill-stone, when unmixed is pure silex. 1850 Lyell 2nd Visit U.S. II. 9 This burr-stone..constitutes one of the members of the Eocene group. |