Gem Focus – April 2025 – Featuring Anthill Garnet: the pyrope unearthed with the help of insects
*Gem Focus & Market Pulse (Free Subscriber)Gemstone mining is anything but an easy task. But for one small group of hardworking insects, finding and moving gem material is simply a by-product of the work done to create their homes.
Enter the anthill garnets found on the Navajo Indian Reservation in Arizona. Anthill garnets get their name because of how they are found and collected, which is by hand after ants (specifically, southwestern harvester ants) have pushed the rough up and out of the earth as they are tunneling and building. The stones gather at the base of the anthills, making them easily to collect from the ground.
According to supplier Columbia Gem House, the stones there have been collected since before the 1850s. They were used in Native American cultural ceremonies in the 1900s and still have spiritual meaning to many today.
(Navajo families have been gathering anthill garnet on their land for generations. To read the firsthand account of the process that Columbia Gem House’s sourcing partner, Jaymus, performs when gathering, including the prayers and traditions that have been passed down, visit ColumbiaGemHouse.com.)
1 mm to 3.5 mm anthill garnet rounds.
(Image courtesy of Columbia Gem House)
According to an article titled “Ant Hill Garnets: Tiny Miner Treasures” in Rock & Gem magazine, anthill garnets can be found in other parts of the world where there are similar conditions, but the Southwest U.S. is the primary and most well-known source.
The orangey-red to dark red pyrope garnets generally are found in small sizes, rarely exceeding 1 carat in size. Given their saturated red color, the material becomes darker the larger it gets, SSEF gem lab said in a report about its research into the material last year; so, one finds more vibrant, bright reds in melee and smaller sizes and more of the deep reds in the larger sizes. The lab also found in its research that the darker reds get their color primarily from chromium, while the presence of iron is much more important to the color of the orangey-red garnet.
Arizona anthill garnet and gold stackable ring.
(Photo credit: Sami Fine Jewelry)
Anthill garnet is often found in traditional round cuts, according to Columbia Gem House, which it said is the best style for exhibiting the reds of this material, but the company did note that it also has nice color in melee rounds.
Anthill garnet is generally found in clear qualities with little to no inclusions, especially in smaller sizes, and therefore needs no treatment.