Danish oil is a wood finishing oil, made of either tung oil or polymerized linseed oil. Danish oil is a hard drying oil, meaning it can polymerize into a solid form. It can provide a hard-wearing, water-resistant satin finish, or serve as a primer on bare wood before applying paint or varnish. It is a "long oil" finish, a mixture of oil and varnish, typically around one-third varnish and the rest oil.