indigotin

[ in-dig-uh-tin, in-di-goht-n ]

/ ɪnˈdɪg ə tɪn, ˌɪn dɪˈgoʊt n /

Origin of indigotin

First recorded in 1830–40; indigot(ic) + -in²

The process for estimating the value of indigo given under Indigo is a good process for obtaining Indigotin.

Cooley's Cyclopdia of Practical Receipts and Collateral Information in the Arts, Manufactures, Professions, and Trades..., Sixth Edition, Volume I |Arnold Cooley
To neutralise this purple effect, a small quantity of a yellow dyestuff and a trifle of indigotin are added.

The Chemistry of Hat Manufacturing |Watson Smith

indigotin

/ (ɪnˈdɪɡətɪn, ˌɪndɪˈɡəʊ-) /

another name for indigo (def. 1)

C19: from indigo + -in