“An intense orange red found on old masters' palettes. It is very opaque, good tinting strength, smooth grained and makes a "long" paint. Note: Red lead has a shelf life. Please contact [Natural Pigments] for more information. Minium is liable to discolor in the presence of hydrogen sulfide, which is present in air pollution. It may also react when mixed with sulfide pigments, such as cadmium pigments. In oil paint it is fairly permanent, however, some have noted that when mixed with white lead, it tends to fade rather than turn dark. Red lead oil paint dries the quickest of all pigments and for this reason we use only 98% lead tetroxide, add a small amount of aluminum stearate (less than 2%), and make only small batches to avoid hardening in the tube. This is done to prevent hardening in the tubes quickly, but will not prevent it entirely.” -Natural Pigments