SEPIA is a valuable and much used deep brown pigment obtained from the ink-sacs of various species of Cuttle-fish (q.v.); that from which it is principally obtained is Sepia officinalis, a native of the Mediterranean, and especially abundant in the upper parts of the Adriatic, where it is a prized article of food. To obtain sepia the ink-sac is, immediately on the capture of the animal, extracted from the body and speedily dried to prevent putrefaction. The contents are subsequently powdered, dissolved in caustic alkali, and precipitated from the solution by neutralizing with acid. The precipitate after washing with water is ready to make up into any form required for use.

Sepia-bone or cuttle-bone consists of the internal “shell” or skeleton of Sepia officinalis and other allied species. It is an oblong convex structure from 4 to 10 inches in length and 1 to 3 inches in greatest width, consisting internally of a highly porous cellular mass of carbonate of lime with some animal matters covered by a hard thin glassy layer. It is used principally as a polishing material and lor tooth powder, and also as a moulding material for fine castings in precious metals.