Fishing weight - Canoe Breaker - Throwing Hammer. Circumference (length ways): 17 1/4 inches, Circumference (Width ways): 14 inches, Color: Light Greyish Brow, Characteristics: Lava rock more or less spherical with a knob on one end with which to fasten a cord, Weight: 4 lb. 12.6 oz. As shown above this implement had several uses. It could be used to weigh down fishing nets in times of peace or used to throw as a weapon in times of war to sink canoes or injure opposing forces.