Figure 6.02. Staurolite Pseudomorph Schist. Pseudomorphs of twinned staurolite porphyroblasts visible on a weathered surface in this sample of this Sil-Grt-Bt-Ms-Qtz schist of the Perry Mountain Formation, East Andover Quadrangle, NW Maine, USA. Muscovite and sillimanite are the principle minerals in the pseudomorphs. USA penny for scale. Use your mousewheel to zoom and pan to see details. Click on the "Show Hres" button to see a higher resolution image. John Brady photo.