Tourmaline crystals 2 to 3 cm. It forms tiny blue-green prisms associated with apatite, rutile, zircon and epidote. Tourmaline is common in the many small complex pegmatites exposed in sec. Dark blue to nearly black tourmaline crystals occur in individuals and sprays with separate crystals up to 12 cm. The blue tourmalines may also be zoned, with light blue cores and dark blue rims.
Tourmaline occurs as a widespread accessory mineral in chloritic gneiss exposed in sec.
Green acicular tourmaline crystals up to 1.2 cm. Black tourmaline is also found rarely as crystal segments up to 1 cm. Tourmaline-bearing veins occur in the Hoskins Lake Granite at numerous localities. A particularly well-exposed zone is in railroad cuts north of Hwy N in the SW sec. 1 T.37N. R.20E. , north of Pembine.