Copper based alloy ingots weighed approximately . Precious metals can be dissolved in acid, sorted, and smelted into ingots. The molten metal was poured into granite moulds which produced ingots of tin. It replaced copper cash and various silver ingots called sycees. Those people carried in their vessels silver ingots, gold ingots and amphorae. Bullion took the form of coins, ingots, and jewelry. The uranium metal produced was in the form of derbies, ingots, billets and fuel cores. Also, a large amount of Copper ingots were collected. Switzerland was Dubai's largest supplier of gold ingots, wastes and scrap. Coins, bars, and ingots are traded or collected. Alba produces around 380,000 metric tonnes per annum of extrusion ingots. There were also three blank coins and two small ingots. Controversy has swirled around the provenance of the copper oxhide ingots. Because of tungsten's high melting point, it is not commercially feasible to cast tungsten ingots. The process begins with the production of monocrystalline silicon ingots.