Mastic Medium Tears MastihaShop® 500gr. Mastic is used in the pharmaceutical, perfume and cosmetic industries for beverage, cooking, and confectionery. Mastic is the natural resin of the Pistacia lentiscus var. Chia, which grows only on the island of Chios. According to scientific research, Chios mastic has antimicrobial, anti-inflammatory and healing effects and benefits oral hygiene, gastrointestinal function and skin care.