Revealing zonation in zircons

Revealing zonation in zircons

Cathodoluminescence image of a collection of zircon grains in a polished epoxy mount. Some zircons have igneous cores, some metamorphic zones, both of which are overprinted. Complimentary analysis by SHRIMP U-Pb suggests a long, complicated history of grain growth, dissolution, and re-growth over a period of about 2.5 billion years.