Dumortierite was first identified in 1881 by a French mineralogist who named it in honour of the palaeontologist Eugene Dumortier (1803-1873). Although best known as a light or dark blue coloured stone dumortierite can also be violet, pink or brown and stones can also exhibit and areas of pink and brown are not uncommon. When opaque it can be mistaken for the mineral sodalite due to the similarity in colour and has also been known to have been sold as fake lapis lazuli because it's considerably cheaper.
Dumortierite is found in metamorphic rocks rich in aluminium. The finest grade specimens can be exceptionally beautiful and will often feature a mass of long slender dumortierite crystals within the mineral quartz. Crystals have a vitreous lustre, tend to be quite small and may exhibit pleocroism with colours varying from red to blue to violet. Commercial grade dumortierite that's popular for use as a lapidary material and in particular gemstones, is quartz that's heavily included with dumortierite crystals.
In crystal healing dumortierite is said to be beneficial for patience and for slowing down aggravated and irritated energies. It stimulates communication between the body's various systems and can help with the expression of spiritual ideas and the comprehension of hidden meanings. It's believed to help resolve opposing points of view and when placed on the throat chakra can encourage one to share advice.
Dumortierite can be found in several countries around the world, it's a relatively hard stone which makes it particularly suitable for lapidary purposes. On Mohs scale of mineral hardness dumortierite grades 8 which makes it only slightly softer than corundum.