Gum copal is a resin produced by the sap of forest tree in Indonesia. Due to common impurities and differences in regions, gum copal ranges in color from black to yellow to white. Gum copal has had a wide variety of uses in both past and present times. Primarily used as an incense by ancient civilizations, it also found use as an early form of glue, and traditional medicine for cases such as dysentery, stomach pains, dizziness, and fright.
Today, gum copal is popularly used as incense. It is also used as a varnish or waterproofing material. When it is heated with certain oils, it becomes nearly transparent. It also can be used as an ingredient in adhesives, perfumes, printing ink, paints, and films.
Gum copal is sold primarily two ways. The first way is as powder, which is usually mixed with turpentine to make varnish. The other way is as the natural "rocks" which can then be used in many different ways.
Prime white soft (PWS) is the highest grade of gum copal. It is white in color and 99-100% purity. It is used for making varnish for wood surfaces and it dries to a hard and shiny film. Such varnish is high-luster and resistant to external scratches.
DBB grade is pebble-sized and whitish yellow in color with about 90-95% purity. This is an economy grade, ideal for production of low-end varnishes. Its solubility is good. It can contain some black copal, but it is still easily dissolved in alcohol solvent mixtures. It is the most common grade for use in incense.
White soft (WS) is the lowest grade of gum copal, larger chunks, black in color with about 60% purity. The impurities include tree bark and soil. The powder leftover from the processing of PWS and DBB is usually used for varnish
