chromate salt

1. n. [Drilling Fluids]
A type of salt in which chromium atoms are in the plus-6 valence state, such as potassium chromate, K2CrO4. Chromium compounds of various types have been used in lignite and lignosulfonate and other mud additives to enhance thermal stability. Since the late 1970s, they are prohibited in muds to be discarded offshore and in other environmentally sensitive areas of the US.