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Resinoids are prepared from natural resinous material by extraction with a hydrocarbon solvent, such as petroleum ether or hexane. In contradistinction to concretes, the resinoids are prepared from dead organic material, whereas concretes are derived from previously live tissue. Typical resinous materials are balsams (Peru balsam or benzoin), resins (mastic and amber), oleoresins (copaiba balsam and turpentine) and oleo gum resins (frankincense and myrrh). Resinoids can be viscous liquids, semi-solid or solid, but are usually homogeneous masses of non-crystalline character. Occasionally the alcohol-soluble fraction of a resinoid is called an absolute.

Some resinous materials like frankincense and myrrh are used either to make an essential oil by steam distillation or a resin absolute by alcohol extraction directly from the crude oleo gum resin. Benzoin, on the other hand, is insufficiently volatile to produce an essential oil by distillation: liquid benzoin is often simply a benzoin resinoid dissolved in a suitable solvent or plasticizing diluent.

Like concretes, resinoids are employed in perfumery as fixatives to prolong the effect of the fragrance.