Piedmontite is not a common mineral, but its pleochroic colours are spectacular.  It is a Mn-bearing epidote and occurs in low to medium grade Mn-rich metamorphic rocks.  It has high relief relative to mica (A), quartz (C) or feldspars (B).  The bright yellow to pink pleochroic colours are evident in the different orientations of the grains in A, and in B the euhedral grains are dominated by dark purples to reds.  Interference colours range to fourth order, but are masked by the strong absorption (C).  Twinning on {110} is evident in one grain in C.  Samples are from the Praborna Mn mine in the Italian Alps, the type locality of piedmontite. Fields of view are 2.2 mm across.  A, B, D pp, C x-nicols.