Mastic is the resin of the pistachio bush (Pistacia lentiscus), an evergreen shrub that belongs to the sumac family (Anacardiaceae). The shrub or small tree usually reaches heights of 1 to 3 metres, and can grow up to 8 metres. In a process called scarification, the bark and branches of the pistachio bushes are cut open to allow the resin to slowly pour out. This process happens annually in June.
The Pistacia lentiscus variety grows exclusively on the Greek island of Chios, in the Aegean Sea. "Mastic" means the tears of Chios. The traditional cultivation of mastic has been included in the intangible cultural heritage of humanity by UNESCO since 2014.