DUM-R-01 Origin: Namibia Grade: A+ Dimensions: 05-10g - Approximately 15-25mm 10-20g - Approximately 25-35mm Origin: Namibia Grade: A+ = high Tumbled dumortierite stone from Namibia Sold individually. Weight of 05-10g and 10-20g Shapes and colors may vary from one stone to another. This blue stone was discovered by the French paleontologist Eugène Dumortier (1802 - 1876) during an expedition in the Alps. It was named dumortierite by the French mineralogist Ferdinand Gonnard (1838 - 1923) in honor of the renowned Eugène Dumortier. However, under the name dumortierite, the blue stone has no assigned legend. In fact, its history is very short. Yet, dumortierite has been found at pre-Columbian cemetery sites. However, it turns out that this blue stone had already been identified before being named dumortierite. It was confused with lapis lazuli, sodalite, or azurite. It is only its structure that allowed it to be distinguished. Note that there is also dumortierite quartz. However, this stone was even sold near Lyon as lapis lazuli. The confusion dates back to Antiquity and lasted until the 19th century. However, some knew perfectly well that the lapis lazuli discovered in Lyon was not really lapis. But this information was jealously kept secret by "the Ancient Schools." Nowadays, it still happens that the "Lyon lapis" is actually dumortierite. It should be noted that dumortierite was sometimes called aluminum borosilicate, but this scientific designation was quickly abandoned. Dumortierite is essentially blue in color, but there can also be specimens of purple to brown color. It has a hardness of 7 on the Mohs scale, making it a stone particularly appreciated by jewelers and goldsmiths. It is mainly composed of aluminum silicate and boron (a simple solid body close to carbon) with traces of magnesium and iron. It is the high concentration of aluminum that gives it this blue appearance. Natural dumortierite stone is rather opaque. Thus, this opacity does not allow it to belong to the family of precious stones. It is a fibrous mineral found within metamorphic rocks in areas concentrated in aluminum. Metamorphic rocks are formed during the transformation in the solid state according to certain parameters such as pressure and/or temperature. Dumortierite is mainly used in jewelry making. In specialized stores, it is offered in its natural, raw, or polished state, in the form of an egg, sculpted.