Original: Often an oil such as linseed was boiled with a resin such as pine resin or even frankincense ; these were called ` varnishes ' and were prized for their body and gloss . Other oils occasionally used include poppyseed oil , walnut oil , and safflower oil .
Simplified: These include pine resin , frankincense , poppy seed oil , walnut oil , and in more modern times safflower oil .