It is used as a precipitating reagent for primary and secondary amines forming insoluble reineckates identifiable by color in analytical chemistry for titration endpoints and historically for amino acid derivatives like proline.

Its primary purpose is to form sparingly soluble characteristically colored salts with organic bases for qualitative and quantitative analysis leveraging the large anionic size and charge for selective precipitation.

Reinecke salt monohydrate (NH[Cr(NH)(NCS)]HO) is a dark red crystalline solid coordination complex featuring octahedral Cr(III) coordinated by two trans ammonia ligands and four equatorial isothiocyanato groups with density 1.49 gcm and decomposition above 270C.