Note:  Do not rely on this information. It is very old.

Garancine

Garancine is a. preparation of madder-root, which was formerly very largely employed in the dyeing industry. It is obtained by the action of (1) dilute, (2) strong, sulphuric acid, upon the root. It possesses about four times the colouring-power of the madder itself, and also gives better colours. A poorer quality obtained from spent madder is known as garanceux. Both these, like all other madder extractions or preparations, are now almost entirely superseded by the artificially-prepared alizarine (q.v.), which forms the colour-principle of them all.