Ammonium carnallite

Description

A deliquescent, white salt composed of ammonium magnesium chloride. Ammonium carnallite has been found as an efflorescence on three ceramic objects (Wheeler and Wypyski 1993). It is theorized that the salt was formed following a cleaning procedure in which Hydrochloric acid was used to remove carbonaceous encrustations followed by an Ammonium hydroxide rinse for neutralization.

Synonyms and Related Terms

Ammonium-Karnallit (Deut.)

Physical and Chemical Properties

Composition	NH4MgCl3-6H2O
Molecular Weight	mol. wt. = 148.70

Resources and Citations

• G.Wheeler, M.Wypyski, "An Unusual Efflorescence on Greek Ceramics" Studies in Conservation, 38:55-62, 1993.

• The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 562