ARAGONITE - CaCO3 Good specimen of Aragonite from Santa Eulalia, Chihuahua, Mexico. This specimen is 8 cm (3-1/8") wide by 7 cm (2-3/4") deep by 5.5 cm (2-1/8") high. It is bright and sparkly and makes a wonderful addition to any collection.Fluorescence a bright green under longwave UV light. Item AR001. Weight 0.38 lbs.