Neys Provincial Park, Lake Superior, Ontario, Canada
Neys Provincial Park is east of Thunder Bay on Lake Superior’s north shore. The rocks along this coastline were born of fire. About one billion years ago, magma rose from the depths and formed shield volcanoes. Some of the magma was alkaline and contained high levels of sodium and potassium. It formed the largest alkaline rock complex in North America.
One of the rocks found here is syenite, a coarse-grained pinkish or beige igneous rock. It looks like granite, but contains no quartz. After eons of erosion, cores of the volcanoes’ magma chambers are now exposed at ground level. The beach sand contains the broken-down bits of this ancient rock: pink to yellowish sodium and potassium (alkali) feldspar, black amphibole prisms (in the feldspar grains), and blocky gray-to-cloudy nepheline. The red grain may be natrolite.
The rolling motion of the waves, back and forth, day in and day out, rounds and polishes the grains.