A result of using pigment inks on resin coated glossy or satin/luster paper. In highlight or areas of white in a photo, the printer leaves the area void of any ink. Because ink may surround the area in question, a void or shimmery area can be seen on the paper if held at certain angles. Light is more directly reflected in the highlight areas and can be distracting.
The effect of seeing a flash of bronze color reflecting off pigment inks, particularly in dark and black areas. Sometimes confused with gloss differential.