Tonalite, hornblendite, and gabbro.

Tonalite in upper part of House Mountain metamorphic complex southeast of Boise (~157 Ma), hornblendite and gabbro at South Mountain southwest of Boise (~160 Ma), and tonalite of Continental Mountain at the Canadian border (~168 Ma). (Paleocene and Cretaceous Idaho Batholith and Older Cretaceous and Jurassic Intrusive Rocks).
State Idaho
Name Tonalite, hornblendite, and gabbro.
Geologic age Jurassic
Lithologic constituents
Igneous > Plutonic > Granitic > Tonalite (Pluton)
Igneous > Plutonic > Ultramafic > Hornblendite (Pluton)
Igneous > Plutonic > Gabbroic > Gabbro (Pluton)

Lewis, Reed S., Link, Paul K., Stanford, Loudon R., and Long, Sean P., Geologic Map of Idaho, 2012, Idaho Geological Survey, Geologic Map 9 (M-9); Scale 1:500,000.

NGMDB product
Counties Boundary - Elmore - Owyhee