AUBURN – Maine Audubon is offering a public trip to explore the quarries of Mount Apatite from 9 a.m. to 3 p.m. Sunday, Oct. 8.

Located in the outskirts of Auburn, Mount Apatite’s old feldspar quarries are unique in Maine for offering access to minerals. The ledges and boulders contain easy-to-see examples of quartz, feldspar and mica; prospectors have even found rare green and pink tourmaline, smoky quartz and lepidolite.

Led by Harold Nilsson, who has been a professional geologist for more than 40 years, the trip will begin with a short class on the area’s minerals and geologic features. The group will then explore the quarries’ marine sand deposits and dunes, collect rocks and minerals, and look for clues to how glaciers affected the area.

The trip is $20 for Maine Audubon members, $25 for nonmembers. Advance registration is necessary; to register, phone (207) 781-2330, extension 215.

For more information on other Maine Audubon programs, visit www.maineaudubon.org.