A resin found as crystals in the bark of a tree that grows deep in the jungles of Sumatra and Borneo. It is only produced in old trees, which can be a thousand years old. To obtain it, the branches of the tree are scraped, which causes it to come out mixed with pieces of bark.
In Japan, it is used to scent ink because its calming effect promotes the concentration and serenity necessary for calligraphy.
For the same reason, it is found in many traditional Japanese incenses.