Zinc chromate

[7] K2CrO4 + ZnSO4 → ZnCrO4 + K2SO4 Zinc chromate's main use is in industrial painting as a coating over iron or aluminium materials.

During the 1940 and 1950s it was typically found as the "paint" in the wheel wells of retractable landing gear on US military aircraft to protect the aluminium from corrosion.

This effect can be seen in Georges Seurat's famous painting A Sunday Afternoon on the Island of La Grande Jatte.

[14][15] Zinc chromate putty was used as sealant in addition to two O-rings between sections of the failed solid rocket booster on Space Shuttle Challenger.

[16] Recent studies have shown that not only is zinc chromate highly toxic, it is also a carcinogen because it contains Cr(VI).

NFPA 704 four-colored diamond Health 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroform Flammability 0: Will not burn. E.g. water Instability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogen Special hazard OX: Oxidizer. E.g. potassium perchlorate