Bronze
From Cantr II Wiki
Can be made on a small fire pit, requires 100g copper, 10g tin, 1g phosphorus, 1g zinc, 100g of wood, and requires the use of a stone ingot, yielding 50 grams of bronze. Used in making weapons. Can also be produced using a smelting furnace, same ratios as with a fire pit, but only 2 grams of wood per gram of bronze.