The Garnet Scream
A garnet crystal trapped in a crystallized body of magma, in microscopic thin section. The trail it left as it traveled through the magma resembles Edvard Munch's "The Scream" painting.
Garnets are extremely useful for piecing together the pressure and temperature history of metamorphosed rocks. Their presence indicates that their host rock has reached pressures of at least 1 GPa (22 miles below Earth's surface), and exceeded temperatures of 600ᵒC. This particular garnet, from underneath the Pamir Mountains northwest of the Himalaya, is actually a small piece of a metamorphosed rock that was caught up within a separate body of magma, and held in place while the surrounding magma cooled. With this, we can infer how the magma and the metamorphosed rocks may have interacted at great depths within the earth, several million years ago. I have named this piece "The Garnet Scream" due to its resemblance of Edvard Munch's "The Scream" painting from 1893.