These 1 Pound Copper Bullion Cubes contain roughly 16 ADVP oz of pure copper, and make an excellent option for those looking alternatives to copper rounds and bars. Each one has a design on the top face of the cube that has been engraved with the full square and information from Coppers place on the Periodic Table of Elements. Included in the design is the atomic number of copper, 29, along with its standard atomic weight of 63.546, and its listing of Cu from the table. Other markings include the weight in ounces, the name Copper, and the melting point in Celsius of copper. Copper was first used by mankind in 8,000 BC, but it was not smelted from its ore until 3,000 years later. Copper was, in many ways, the first metal to mark mankinds advancement. Not only was it the first metal used by humans, it was the first smelted, the first to be cast in shapes and molds, and the first to be alloyed with another metal on purpose, in the creation of bronze. Today, copper is commonly found in homes and various other industries. A soft, malleable metal with high electrical and thermal conductivity, it was popular in the use of electrical wiring and water piping. It is also an essential metal to living organisms as a trace dietary mineral with trace respiratory enzyme complexes.