Colemanite is an abundant mineral, and transparent material isn’t rare. However, gem cutters rarely facet these typically pale stones. Difficult to cut and wear, colemanites are better suited for collectors of unusual gemstones.
Colemanite serves as an ore for boron and has many industrial uses. As a gemstone, however, it has weak dispersion, so it shows little fire, and normally occurs colorless. Since it also has perfect cleavage and a hardness of only 4.5, this fragile gem would make an unlikely choice for a jewelry stone.
The southwestern United States, particularly Boron and Death Valley, California, produces beautiful colemanite crystals. Other notable sources include Argentina, Kazakhstan, and Turkey.
Colemanites have considerable heat sensitivity, so any setting in metal jewelry should be done very carefully. If worn as jewelry, they require protective settings. These gems are also slightly soluble in water. Don’t soak these gems during cleaning and make sure they’re dry before storing. Clean them only with a soft brush, mild detergent, and warm water. For more care recommendations, consult our gemstone jewelry cleaning guide.