GUINEA, a gold coin formerly struck and current in Britain, and so denominated because the gold of which the first specimens were struck (temp. Car. II.) was brought from the coast of Guinea; and for a like reason it originally bore the impression of an elephant. The value of the guinea varied greatly at different periods, but latterly it was worth 21 shillings. Its weight was 5 dwts. 9.4125 grs. On the introduction of the sovereign—first coined in 1817—the old guinea coinage was gradually superseded. See COINAGE, and MONEY.