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Carnelian Gemstones

Author: , PhD, GIA Graduate Gemologist

Carnelian gemstone

Carnelian gemstone: A tumble-polished carnelian with typical translucent diaphaneity. Image copyright iStockphoto / Arpad Benedek.


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.

Banded Carnelian tumbled stones

Banded Carnelian: Tumbled stones made from banded carnelian. These stones measure about 1 inch across.

Table of Contents

What is Carnelian?
Carnelian Gemstones
Tumbled Carnelian
More About Carnelian

Carnelian Gemstones

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.

Tumbled Carnelian

Carnelian agate has a hardness of seven on the Mohs Hardness Scale. It tumbles well with stones of similar hardness, 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.

Carnelian agate beads in a necklace

Carnelian agate beads: Carnelian agate beads in a necklace. Image copyright Geology.com.

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.

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