Cobalt(II) thiocyanate is an inorganic compound with the formula Co(SCN)2.

[4] The hydrate may be prepared by the salt metathesis reactions, such as the reaction of aqueous cobalt(II) sulfate and barium thiocyanate to produce a barium sulfate precipitate, leaving the hydrate of Co(SCN)2 in solution:[4] or the reaction of the hexakisacetonitrile cobalt(II) tetrafluoroborate and potassium thiocyanate, precipitating KBF4 The anhydrate can then be prepared via addition of diethylether as an antisolvent.

[1] Detailed procedures for the cobalt thiocyanate test, often sold as the "morris reagent" are available.

[5] Glycerol is often added to stabilise the cobalt complex, ensuring it only goes blue when in contact with an analyte and not due to drying.

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