rosin or colophony, hard, brittle, translucent resin, obtained as a solid residue from crude turpentine. Usually pale yellow or amber, its color may vary from brownish-black to transparent depending on the nature of the source of the crude turpentine. Rosin has no taste but often has a faint odor of pine. It is soluble in alcohol, ether, turpentine, and several other organic solvents, and in solutions of various metal hydroxides. Rosin is not a pure substance but a mixture of several compounds, chiefly abietic acid. It is used in making cements, varnishes, paints, sealing wax, adhesives, and some soaps; for treating violin bows; as a dressing for machine belting; as a sizing material for paper; in the preparation of certain metals for soldering; and, in pharmacy, in some ointments, plasters, and similar preparations. Athletes commonly rub it (in the form of dust) upon their hands or the soles of their shoes to prevent slipping.