The Bear Lake area is situated in the southeast border zone of the Glamorgan Gneiss Complex, which is composed of amphibolite, granite, granitic gneiss and minor amounts of marble. This area is predominantly underlain by quartz - feldspar gneiss and amphibolite, with lenses of pegmatite and bands of marble. This area is famous for apatite, hornblende, titanite, and feldspar. Over time the calcite in the veins dissolves, due to natural acids formed by rain water mixing with leaf litter. As the calcite weathers out, the more resistant silicate minerals are left in the black earth which fills the veins.
Mineral collecting is done by digging into the dirt filled veins, to find the loose lying minerals.
There are mineral specimen and jewellery exhibitors from around the world, swappers, gold panning, mineral identification and many more activities. Over 300 mineral specimens from the area are on display. This guidebook provides mineral collecting tips, mineral descriptions and directions to over 30 popular collecting sites in the Bancroft area.