Musk. Polarised light micrograph of crystals of musk. Musk is an aromatic substance produced as a glandular secretion by the male musk deer. A similar substance is produced by males of certain other mammals, such as the civet and otter. It is also produced by some plants. In mammals, musk may serve as a territorial marker & sexual attractant. It is a sought after odour in the perfume industry, used particularly in mens toiletries. Musk is artificially synthesized for perfumery. In its artificial form of 2,4,6-Trinitro-3-tert- butyltoluene (chemical formula: C11.H13.N3.O6), it is known as musk baur. Magnification: x50 at 4x5 inch size, x30 at 6x7cm.