Its colour varies from brilliant bluish-grey to deep red.
The small horns and bluish-grey colour of the adult bulls serve to distinguish the Indian nilgai, Boselaphus tragocamelus, from the other members of the subfamily.
The Concord granite is a medium bluish-grey coloured muscovitebiotite granite, with mica plates so abundant as to effect the durability of the polish of the stone; it is used for building-the outer walls of the Library of Congress at Washington, D.C., are made of this stone-to a less degree for monuments, for which the output of one quarry is used exclusively, and for paving blocks.
The back of the Russian squirrel has an even close fur varying from a clear bluish-grey to a reddishbrown, the bellies in the former being of a flat quality and white, in the latter yellowish.
The best are the full furred ones of a very pale bluish-grey with fine flowing black top hair, which are obtained from the Hudson Bay district.
The underwool in all sorts is generally of a bluish-grey tone, but the top hair in the depth of winter is usually full enough in quantity to, hide any such variation.
The hills on the right bank Geology, of the Tiber culminating in Monte Mario (455 ft.) belong to the first of these, being of the Pliocene formation; they consist of a lower bluish-grey clay and an upper group of yellow sands and gravels.
If silver nitrate salts be administered for a long period as a medication, the skin that is exposed to light becomes of a bluish-grey colour, which is extremely persistent.