Ibn Umar, when he perfumed himself with incense, would use unscented aloeswood, and camphor which he would add to the aloeswood. Then he said, "This is how the Messenger of Allah ﷺ used to perfume himself with incense."
كان ابن عمر إذا استجمر استجمر بألوة، غير مطراة، وبكافور يطرحه مع الألوة، ثم قال: هكذا كان يستجمر رسول الله ﷺ.
Muslim narrated it in the Chapter on Words of Etiquette (2254) through several routes from Ibn Wahb, who said, Makhrama told me, from his father, from Nafi, and he related it.His saying, "yastajmir" - here istijmar means using perfume and fumigating oneself with it, taken from "mijmar," which is incense.His saying, "aluwwah," with the hamza either open or closed, and the lam closed, refers to the aloeswood that is used for fumigation.His saying, "ghayr mutarraah" means not mixed with any other perfume.