A resin (plant resin) is a thick, sticky liquid exuded by some plants as a defense mechanism against predators. This resin can be collected by humans and used for various purposes. Witches often use resins for incense and to add to oil blends.
When the bark of certain trees is damaged, it “bleeds” resin which may trap an insect or the chemicals contained within may prove unpleasant to predators and drive them away. The chemicals within the resin may also prove healing to the tree, preventing the introduction of pathogens to the wound. Humans have long been collecting resin from trees to use as glue, varnish, incense, fragrance, and medicine.
Resin is not soluble in water but can be dissolved into alcohol and many can also be dissolved into oils, though heating is often required. Resins can be burned directly and tend to produce a lot of smoke.
Some examples of resins used in magick include copal, frankincense, myrrh, dragon’s blood, pine, and amber.