Dumortierite

About Dumortierite

Named after French paleontologist Eugene Dumortier. It is one of the few naturally blue minerals that is hard enough for jewelry. It is often found in quartz, creating blue denim-like patterns in the stone. It is used as a ceramic additive to reduce thermal expansion. Brazil and Madagascar produce the best specimens. It can be confused with lapis lazuli but is harder. It takes an excellent polish. It is relatively inexpensive. It is found in metamorphic rocks.