PROBLEM TO BE SOLVED: To provide a labeled additive for a food product, medicine, or feed, capable of identifying a food product, medicine, or feed, a manufacturing method for the same labeled additive, and an identification method of a food product, medicine, or feed.SOLUTION: After washing unburnt shell, an organic substrate is carbonized and ashed in a primary heat-treatment in air within 400°C-600°C. Then, the shell cooled to about room temperature is pulverized, and a secondary heat-treatment is carried out in CO2 atmosphere in 800°C-900°C, whereby shell powder is obtained. The intensity ratio of three light emission bands of a light emission spectrum of the shell powder, is used to assign an identification number, and calcium carbonate obtained from the shell is used as a main component, by the labeled additive for a food product, medicine, or feed. By adding the labeled additive to a food product, calcium fortification and quality improvement is provided, and by measuring the light emission spectrum of a sample remaining after ashing this food product, the food product, medicine, or feed is capable of easily being identified.
