Iron is a common element. In the Adirondacks, it is usually found in the form of magnetite. Magnetite is an iron ore that is attracted to magnets. This unique quality was described in the mid 1700s by Swedish scientist, Peter Kalm.

Kalm was exploring the region and noticed that “the kinds of sand… found on the Lake Champlain; one is black and the other garnet colored. All of the grains of this sand without exception are attracted to the magnet.”

Iron ores can be processed in forges and furnaces to make cast iron, wrought iron, and steel.