Meaning and Properties


Deep blue dumortierite is called the "blue denim stone." It is named for a French paleontologist, Eugène Dumortier, who discovered it in 1881 in the Rhône-Alps region of France. Dumortierite is used to manufacture high grade porcelain. It is sometimes mistaken for sodalite and lapis lazuli. Because of the perceived similarity, dumortierite is often used as a cost-saving substitute for lapis which costs two to three times as much.

Metaphysical Properties

Dumortierite is believed to be a stone of self-reliance and discipline. It is said to promote patience and orderliness. The stone is credited for promoting insight and aiding memory.

Geological Properties

Dumortierite crystals are formed most often in metamorphic rocks that are rich in aluminum and under high temperatures. The vitreous crystals' colors range from brown to blue and green, as well as more rare pink and violet. Color variations occur with the substitution of iron and other elements for the aluminum.

Dumortierite is found in Brazil, Europe, Sri Lanka and Peru, as well as both the United States and Canada.

Mineral Information Aluminum borate silicate
Chemical Composition Al7(O3(BO3)(SiO4)3)
Color Dark blue to violet blue
Hardness 7 (Mohs)
Specific Gravity 3.26 - 3.41
Refractive Index 1.686 - 1.723

Proper Care of Dumortierite

Dumortierite is fairly hard (Mohs hardness 7), so it can be cleaned with an ultrasonic cleaner. It can also be cleaned with warm, soapy water. Let it air dry and store away from other metals or gemstones that might damage the surface. Remove dumortierite jewelry when doing heavy work that might scratch it--such as gardening or mechanics.

To learn more about dumortierite and other gemstones, order your copy of Walter Schumann's revised and expanded edition of Gemstones of the World.

Designing with Dumortierite

Dumortierite beads are ideal for wherever you want the look of lapis lazuli at a fraction of the cost. Both the young and the young at heart love this stone in everything from necklaces to bead strands for their hair. Like lapis lazuli, it appeals to both men and woman. That makes sense given the widespread popularity of blue jeans.

View more resources featuring dumortierite, including Design Ideas, Videos, Tutorials and more!

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