Alstonite, also known as bromlite, and alstonite by August Breithaupt of the Freiberg Mining Academy in 1841, after Alston, Cumbria, the base of operations of the mineral dealer from whom the first samples were obtained by Thomson in 1834. Both of these names have been in common use. The faces are horizontally striated perpendicular to the pseudohexagonal c crystal axis and they are divided vertically by a medial, slightly reentrant twinning line parallel to the pseudohexagonal c axis. Similar crystals have been found at Fallowfield.
- England: Alstonite has been found in veins at New Brancepeth, near Durham.