Rock Type: Garnet amphibolite
Location: North Bay, Ontario
Description: Large to coarse-grained garnet (black) and amphiboles (brighter colours) defining a diagonal orientation. Relatively large plagioclase (grey and white striped or “twinned”) is intergrown with the garnet and amphibole. The rock was studied for its industrial garnet potential. Garnets grow under high pressure and therefore formed from cooling magma that injected deeper in the crust or was subject to pressure after it formed.