Manufacturers of formula feed use large mixers when making animal feed. If the feed is not completely mixed, portions will contain either too much or too little of the formulated critical microingredients. Microtracers are colored, uniformly-sized iron particles and are a valuable tool to validate completeness of mixing. Mark has extensive experience with Microtracer recovery and interpretation of count data. He regularly provides US and international customer support and has developed sampling equipment and published the associated methods. Mark is a CA Master beekeeper, a Returned Peace Corps Volunteer and interested in water disinfection research.