English: Three reproductions of bronze age knives. The knive on the left has been cast using arsenical bronze (approx. 8%wt As) and shows the typical silverish sheen of arsenical copper alloys. The knives in the center and on the right were cast in tin bronze (CuSn15 and CuSn12, respectively). CuAs8 can be cold-worked to a hardness similar to a CuSn8 alloy and shows similar properties alike. When arsenic content rises above 8%wt the bronze becomes brittle and is of no advantage.