Walk to the water’s edge and your eye is drawn to what appears to be shiny red and black sand. The ‘sand’ is actually magnetic and is a not really sand at all!

Magnetite in the sand
Magnetite in the sand

The shiny black specks are minerals of magnetite while the red grains are garnet. They are deposits from the Canadian Shield which were broken off by the scouring action of the Laurentide Ice sheet and later left in glacial deposits around the Great Lakes.

Wave action from the glacial lakes eroded the glacial deposits and then sorted by the currents. Heavier minerals with high densities such as magnetite and garnet were separated from the lighter low density minerals such as quartz and feldspars.

By sorting the minerals, the heavy magnetite and garnet were concentrated together along the shoreline while the white quartz and feldspars were carried further by the current and away from the shoreline.

Challenge: Magnetic Attraction!
Take a pinch of the ‘black sand’ to the sign post where there is a magnet. Hold it close to the magnet and see what happens!

Magnetite is an iron oxide.

Next Up:
For the Bonus Stop #11 scan its QR code right now!