(uncountable, uncommon, dated) A pale greyish white colour, tinted with blue.
1830, John Burnet, A practical treatise on painting, In nature we as often find the light cool as warm; also in the pictures of many of the Flemish and Dutch schools, where, as Sir Joshua himself mentions, " the silver gray or pearly is predominant, and are valued by the connoisseurs in proportion as they possess this excellence of a silver tint."
1884, Pearly is that silky and often coloured lustre which renders of such value
1899, When (the scales are) more developed and thickened, the color (pearly) is deepened, shading
