vugn.

1818 W. Phillips Outl. Mineral. & Geol. (ed. 3) 207 The sound which the miner hears, may reasonably be accounted for by presuming him to be at work in the immediate neighbourhood of a cavity, or as he terms it, a voog.

1835 E. Pearse Let. in A. E. Bray Descr. Part Devonshire (1836) III. xxxix. 256 It is not uncommon in deep mines, where there are what the miners term vugs..to hear loud and frequent explosions.

1855 J. R. Leifchild Cornwall: Mines & Miners 92 Above this mixed mass, and in the level above, a great cavity (called by miners a vugh) was found.

1883 Encycl. Brit. XVI. 445/2 Dynamite..is very effective even in ground full of ‘vughs’ or cavities.

1927 M. Terry Through Land of Promise vi. 90 In places there are small ‘vugs’ containing quartz crystals.

1953 Amer. Mineralogist 38 7 The vugs are commonly almond-shaped and range in size from 10 cm. down to microscopic dimensions.

1976 Nature 29 Apr. 813/1 The eye is captivated by the beautiful scanning electron microscope photographs of iron crystals deposited in vugs.

1864 W. W. Smyth Catal. Min. Coll. Museum Pract. Geol. 12 The lode is full of cavities, or ‘vuggy’ (as the Cornish miners term it).

1883 W. S. Gresley Gloss. Terms Coal Mining 273 Vughy rock, a stratum of cellular structure, or one containing many cavities.

1953 Amer. Mineralogist 38 7 Some of the replaced rock has a very vuggy texture.

1970 E. C. T. Chao et al. in Proc. Apollo 11 Lunar Sci. Conf. I. 65 Pyroxferroite was first recognized by the LSPET (1969) as an unidentified yellow mineral that seemed to be concentrated in vuggy areas of the Type B rock.

1971 V. A. Firsoff Gemstones Brit. Isles iv. 25 Amethyst occurs in druses and ‘small vuggy veins’ in the former haematite mines of Mwyndy and Garth Ward.