Rosin, formerly called colophony or Greek pitch (Pix grca), is a solid form of resin obtained from pines and some other plants, mostly conifers, produced by heating fresh liquid resin to vaporise the volatile liquid terpene components. It is semi-transparent and varies in color from yellow to black. At room temperature it is brittle, but it melts at stove-top temperatures. It can be used as a constituent of varnishes, waxes and filler compounds. See 'Turpentine'.