Now you can buy Red Carnelian Agate mined directly from the Norcross-Madagascar (NMG) Carnelian Quartz quarry. Red Carnelian rough and Carnelian carvings including Carnelian hearts, Carnelian spheres, Red Carnelian Gemstones and more are available at Madagascar Minerals®. Sometimes Carnelian is spelled Cornelian. Red Carnelian is an Agate Chalcedony gemstone. It could be referred to as Carnelian Agate or Carnelian Quartz.