Sumi ink

Inksticks (Chinese: 墨  Mò; Japanese: 墨 Sumi; Korean: 먹 Meok) or Ink Cakes are a type of solid ink (India ink) used traditionally in several East Asian cultures for calligraphy and brush painting. Inksticks are made mainly of soot and animal glue, sometimes with incense or medicinal scents added. To make ink, the inkstick is ground against an inkstone with a small quantity of water to produce a dark liquid which is then applied with an ink brush. Artists and calligraphers may vary the thickness of the resulting ink according to their preferences by reducing or increasing the intensity and time of ink grinding.

Along with the inkstone, brush, and paper, the inkstick is considered one of the Four Treasures of the Study of classical Chinese literary culture.

The earliest artifacts of Chinese inks can be dated back to 12th century BC, with the use of charred materials, plant dyes, and animal-based inks being occasionally used, with mineral inks being most common. Mineral inks based on materials such as graphite were ground with water and applied with brushes. The mineral origins of Chinese inks were discussed by the Eastern Han dynasty scholar Xu Shen (許慎, 58 – c. 147). In his Shuowen Jiezi, he wrote "Ink, whose semantic component is 'earth', is black." (墨，從土、黑也), indicating that the character for "ink" (墨) is composed of the characters for "black" (黑) and "soil" (土), due to the earthly origins of the dark mineral used in its production.

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