| 释义 |
▪ I. costean, costeen, v. Cornish Mining.|kɒˈstiːn|
[See quot. 1778. But Jago has ‘wood-tin, costean, an ore of tin in structure like wood’, f. cos, M.Cornish coid wood + stean tin.]
intr. To sink pits down to the rock in order to ascertain the direction of a lode. Usually coˈsteaning vbl. n.
1778W. Pryce Min. Cornub., Another way of discovering Lodes is by sinking little pits through the loose ground down to the fast or solid country..This way of seeking the Tinners call Costeening, from Cothas Stean; that is fallen or dropt tin. 1850Ansted Elem. Geol. 500 Where their actual presence is doubtful..a series of experiments called in Cornwall ‘costeaning’, is undertaken with the view of discovering the presence of a vein. 1880M. A. Courtney W. Cornw. Gloss., Costeening, examining the back of a lode by digging pits. 1884R. Hunt Brit. Mining 502 The pits or shafts sunk are costeaning pits or shafts.
▪ II. costean, costeen, n. Cornish Mining.|kɒˈstiːn|
[See costean v.]
A pit sunk down to the rock in costeaning. Also costean pit.
1778W. Pryce Min. Cornub. 319 Costean pits are shallow pits to trace or find Tin. Costeaning, ditto. 1895Daily News 22 Oct. 2/1 No. 3 Reef, Eldorado, has been proved by costean pits for a length of 450 ft. 1896Westm. Gaz. 20 Apr. 8/1 A costeen has exposed the cap of a reef 4 ft. wide of solid quartz. 1897Daily News 19 Jan. 2/2 Recently two separate reefs have been struck in separate costeens. Ibid. 16 Feb. 8/1 A costeen over 100 feet in length has cut a strong reef 3 feet wide. 1920Glasgow Herald 31 Mar. 11 The White Hope..has been opened up all along the line of lode by costeens. 1964A. Nelson Dict. Mining 109 Costean, (1) A trench cut across the conjectured line of outcrop of a seam or orebody to expose the full width. (2) The channel eroded by a flow of water to expose mineral deposits during prospecting work. |