Rock Tumblers » Gemstones » Carnelian
What is Carnelian?
Carnelian agate is a name given to a translucent orange to red to brown chalcedony. It is frequently a banded material with bands of red to orange chalcedony alternating with bands of white agate.
Carnelian is a popular semiprecious gemstone and one of the most frequently tumbled agates. It is also cut into cabochons, beads and sometimes carvings. Carnelian is a hard, tough stone and works well in most jewelry uses. Its bright color makes it a popular and desirable gemstone that can be obtained at a reasonable price.
Carnelian agate has a hardness of seven on the Mohs Hardness Scale. It tumbles well with similar hardness stones such as agates, jaspers, and quartz materials. It is a good tumbling rough for people who are new to rock tumbling because it easily tumbles to a high polish.
More About Carnelian:
A large amount of the material sold as carnelian is actually a more common and less colorful agate that has been heat treated or stained. Heating causes iron impurities within the agate to develop a bright orange to bright red color.
|Carnelian agate beads in a necklace. Image © Geology.com.
|A tumble-polished carnelian with typical translucent diaphaneity. Image © iStockphoto / Arpad Benedek.