Enamel paint refers to an oil based paint that dries to a hard, normally high gloss, weather resistant finish. It is used extensively by sign painters and can be applied to glass, metal, plastic, canvas and wood with ease. The paint itself is usually alkyd based and is made by mixing oil paint with a large amount of varnish, providing a semitransparent or opaque glasslike substance. Fine artists have also been known to use commercial enamel paint in their work including Pablo Picasso, Jackson Pollack, Hermann-Paul and Sidney Nolan.