Is it getting hot in here? The pressure is certainly rising.
Today’s deskcrop is a piece of the Powell kyanite schist from northern Wisconsin. This is an absolutely gorgeous rock, particularly in thin section. If you take a close look around the full scale version of the image below you’ll see both weathered (bottom) and fresh (top) surfaces of this rock. The keen eyed observer will be able to distinguish porphyroblasts of red garnet and pale blue kyanite among the mass of biotite, muscovite, plagioclase, and quartz grains that make up the bulk of this rock.
I think we’ll give the metamorphic theme a rest for the weekend, but when we come back on Monday you can expect to see a sillimanite zone rock in this space.
Explore this and all of my 2010 Deskcrops and Outcrops in Google Earth!