Collecting and collecting the inner shell peeled from the mullet; Or in April-August, the inner shell of mullet floating by the sea is fished out, washed and dried.

The method removes impurities, washes, dries and breaks into small pieces. This product is mostly irregular or square flake, white or yellowish, and has a light taste.

Processing of cuttlebone: cleaning, drying in the sun and mashing into small pieces. Stir-fry cuttlebone: stir-fry cuttlebone blocks with slow fire until they are yellow. Calcination of cuttlebone: put cuttlebone into a pot, calcine until dark brown, take it out and let it cool.