Microingredient containing tracer

摘要

A tracer particle for determining the concentration of a microingredient in a bulk material is disclosed. The tracer particle comprises a finely divided ferromagnetic particulate material approximately 90% of which is approximately 325 mesh or smaller, a microingredient and a binder wherein the microingredient and ferromagnetic material are entrapped in the binder and wherein the tracer particle is approximately 35 to 80 mesh in size.