Description

Lake Superior Agate is a type of agate stained by iron and found on the shores of Lake Superior. It is the oldest and one of the most beautiful types of agate found in the world. This agate differs from others in its rich red, orange, and yellow coloring, a result of iron oxidation. Believed to be 1 to 2 billion years old. Lake Superior Agate formed in the Lake Superior area lava flows. As the lava cooled, water vapor and carbon dioxide became trapped as gas pockets. Later ground water carrying feric iron, silicates and other dissolved minerals passed through these pockets. Over time these solutions crystallized into concentric bands of fine grain quartz called Calcedony (agate). The concentration of iron and amount of oxidation determine the color within or between an agate’s bands.