The CPI takes a constant basket of goods and sees how the price changes from year to year. If the price of the basket of goods increases, then there is price inflation. If the price of the basket of goods decreases, then there is deflation.
Copper and tin mainly make up bronze but other elements include phosphorus, manganese, silicon and aluminium.
Bronzesmiths make bronze by melting two different metals and mixing them. The two metals are copper and tin. Copper, by itself, is too soft to make tools of.