Silver Buttons
Navajo indians in the American Southwest made silver buttons by hammering buffalohead nickles into a dome shape and soldering an eyelet onto one side. They also used dimes, but those would be very small buttons.
Since silver is soft and easy to work it has always been a popular metal for ornamental items. A button is both decorative and functional so they were popular. Since their manufacture doesn't require a lot of material they are very affordable.