Preparation method of standard substance for detecting harmful heavy metal in ornaments

The invention relates to a preparation method of a standard substance for detecting harmful heavy metal in ornaments. Zinc powder, lead powder and cadmium powder with certain purity are uniformly mixed according to a certain mass ratio; the mixture is put in an ultrasonic instrument to be oscillated for a half hour to be prepared into a presmelting raw material; about 0.5kg of presmelting raw material is put into a graphite crucible; a layer of active carbon powder is added at the surface for preventing oxidization; then, the presmelting raw material is put into a vacuum melting furnace; certain initial induction current is set for heating smelting; after the smelting, samples are injected into a silica gel mold for cooling; the samples are taken out; the standard substance for detecting harmful heavy metal of lead and cadmium is prepared, and is dried to be placed; the obtained standard substance samples are cut and ground into semicircular particles with the diameter being 5+/-0.5mm and the thickness being