Black Indies, n. — Green’s Dictionary of Slang

Black Indies n.

[the Indies, whether East or West, were the sources of great mercantile wealth; black implies the area’s mines]

Newcastle upon Tyne, in its role as a centre of coal-mining.

c.1698		B.E. Dict. Canting Crew n.p.: Black Indies Newcastle, from whence the Coals are brought.
1725		New Canting Dict.
1737		Pope Mother Gin 29: Nor the whistling of the Southern gale, Which tow’rds Black-Indies drove me scap’d from jail.
1759, 1760, 1776		Bailey Universal Etym. Eng. Dict.
1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue.
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue n.p.: black indies, Newcastle in Northumberland, whose rich coal mines prove an Indies to the proprietor.
1835		G. Kent Modern Flash Dict.
1848		Flash Dict. in Sinks of London Laid Open.
1867		W.H. Smyth Sailor’s Word-Bk (1991) 104: Black Indies. Newcastle, Sunderland.