Danburite is a calcium boron silicate mineral with a chemical formula of CaB2(SiO4)2.

The Dana classification of minerals categorizes danburite as a sorosilicate, while the Strunz classification scheme lists it as a tectosilicate;[4] its structure can be interpreted as either.

The clarity, resilience, and strong dispersion of danburite make it valuable as cut stones for jewelry.

It is named for Danbury, Connecticut, United States, where it was first discovered in 1839 by Charles Upham Shephard.

[5] This article about a specific silicate mineral is a stub.