fusainn.

1883 Jrnl. Chem. Soc. 44 941 Fusain is a variety of coal, resembling wood-charcoal in appearance. Some stalks, the interior of which is composed of fusain, are covered with a bark which has been converted into coal.

1913 Proc. Amer. Philos. Soc. 52 89 The unaided eye can discern many features of coal in the bed; it can group types into glance, matt, cannel, fusain.

1919 M. C. Stopes in Proc. Royal Soc. B. 90 472 These four distinguishable ingredients, all of which..are to be found in most ordinary bituminous coals, I name provisionally as follows:—(i) Fusain. (ii) Durain. (iii) Clarain. (iv) Vitrain. Together the equivalent of ‘bright’ or glance coal of various authors.

1935 Nature 23 Nov. 818/2 Quite moderate variation in the amount of fusain in the coal has important effects on its utility.

1961 W. Francis Coal (ed. 2) v. 296 Fusain differs very considerably in constitution and properties from the remaining ingredients of coal.

1961 W. Francis Coal (ed. 2) v. 296 The proportion of fusain in most coals is small, generally less than 3%.

1918 M. C. Stopes & R. V. Wheeler Monogr. Constit. Coal 22/2 The two terms ‘carbonised wood’ and ‘mother of coal’..are both open to grave objections... We therefore propose to adopt the Anglicised form of the French word, fusain, as is done by Stevenson (1911–13). We suggest also..for the process of forming fusain, fusainization.

1918 M. C. Stopes & R. V. Wheeler Monogr. Constit. Coal 22/2 We suggest..fusainized as the corresponding adjective.