The heraldic scholar A. C. Fox-Davies proposed that, in some circumstances, "white" should be considered a heraldic colour, distinct from "argent". In a number of instances, a label or collar blazoned as "white" rather than "argent" appears on a supporter blazoned argent "or" or. The use of "white" in place of "argent" would be consistent with the practice of heraldic blazon that discourages repeating the name of a tincture in describing a coat of arms, but if it were merely intended as a synonym of "argent", this placement would clearly violate the rule against placing metal on metal or colour on colour (see below). This difficulty is avoided if "white" is considered a colour in this particular instance, rather than a synonym of "argent". This interpretation has neither been accepted nor refuted by any heraldic authority, but a counter-argument is that the labels are not intended to represent a heraldic tincture, but are in fact white labels proper.