Eudialyte should more properly be described as a member of the Eudialyte group. Samples are seldom analysed enough to narrow identification further. It is found in alkaline igneous rocks.
Alkaline igneous rocks contain more alkalines than can be explained by feldspars alone. They have an odd mineralogy, and are famous for large concentrations of rare earth elements. These elements are needed for mobile phones and electronics. REEs are found in relatively high concentrations in eudialyte making this a commercially important mineral.
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