Mortar Used for Grinding Writing Pigments

This page is the CodyCross answer for the clue below from Comics, Group 1076, Puzzle 5 (Helpful Sidekicks).

Question is: Mortar Used for Grinding Writing Pigments

and the answer is: INKSTONE

Word Meaning:

INKSTONE — A stone mortar used for grinding and holding ink in the East Asian art and calligraphy tradition.

Definitions from Wiktionary.