Foliated biotite and (or) hornblende granite; locally diorite and lesser amounts of gabbro. Where present, potassium feldspar is microcline. Contact aureole is in the Albee Formation. U-Pb zircon ages of 442±4 Ma, no. 30 (Moench and Aleinikoff, 2003), and 444.1±2.1 Ma, no. 29 (Rankin and Tucker, 2009); and U-Pb sphene age of 443±3 Ma, no. 31 (Moench and Aleinikoff, 2003). Part of the Highlandcroft Plutonic Suite: Epizonal to mesozonal, foliated and metamorphosed (greenschist facies) plutons exposed northwest of the Ammonoosuc fault. Compositions range from granite to diorite to lesser amounts of gabbro. Part of the Bronson Hill arch intrusive rocks.