Mirond or Zircon is a common mineral in all types of igneous rocks throughout Middle-earth. Gems are normally found as rounded grains in stream and beach sands, often with mal deposits. Mithgîn and other precious metals are typically melted in crucibles made of zircon.The colours of Zircon may vary but red is most valued.
- MERP Rulebook 2nd Edition
- The Gems of Middle-earth, online essay by William E Wilson