The Lydian King Alyattes started to forge coins during this peace period. The first coins were made from electrum, an alloy of 55 % gold, 45 % silver and a small amount of bronze. Since the Stream of Gediz and the Stream of Pactolus running through Sardis were rich in gold content, the Lydians collected this gold and became a rich nation. These coins began to be used for trading and became widespread, bringing in trade via coins instead of animals.