Gamboge
Gamboge is a deep-yellow pigment derived from a species of tree that primarily grows in Cambodia. Popular in East Asian watercolor works, it has been used across a number of media dating back to the 8th century. Easy to transport and manipulate into a durable watercolor paint, gamboge is a versatile pigment that has been used in paintings, printing of books, and garment dyes, including the robes of Buddhist monks. Gamboge is toxic to humans, and is potentially deadly in large doses. Due to its toxicity and poor lightfastness, gamboge is no longer used in paints, though limited use continues in other contexts. However, gamboge does not react well with lime surfaces, making it unsuitable for frescos and with white lead. Despite its popularity, gamboge usage has not been extensively examined in works of art from any time period. The few instances where art historians have checked for the pigment in a given work have confirmed its widespread use and its longevity as staple in watercolor painting particularly in eastern art.
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