Rare US Dollar Bill

The U.S. dollar is the currency most used in international transactions and is one of the world's reserve currencies. Several countries use it as their official currency, in many others it is the de facto currency, and it is also used as the sole currency in some British Overseas Territories.
Overview
The Constitution of the United States of America provides that the United States Congress shall have the power "To coin Money". Laws implementing this power are currently codified in Section 5112 of Title 31 of the United States Code. Section 5112 provides in which forms the United States dollars shall be issued. Those coins are both designated in Section 5112 as "legal tender" in payment of debts. The Sacagawea dollar is one example of the copper alloy dollar. The pure silver dollar is known as the American Silver Eagle. Section 5112 also provides for the minting and issuance of other coins, which have values ranging from one-hundredth of one dollar to fifty dollars. These other coins are more fully described in Coins of the United States dollar.