cedarwood oils each have characteristic woody odours which may change somewhat in the course of drying out. the crude oils are often yellowish or even darker in colour and some, such as texas cedarwood oil, are quite viscous and deposit crystals on standing. they find use (sometimes after rectification) in a range of fragrance applications such as soap perfumes, household sprays, floor polishes and insecticides. small quantities are used in microscope work as a clearing oil.