Tumbaga is an alloy comprised mostly out of gold and copper and was used very frequently in ancient American civilizations. The ratio of gold to copper varies wildly; some items have been known to contain as much as 97 percent gold or 97 percent copper. Some tumbaga has also been found to comprise up to 18 percent of other assorted metals.

In 1992, approximately 200 tumbaga bars were recovered in wreckage off of Grand Bahama Island. These are the best examples available of tumbaga artifacts.

Some scholars believe that the Golden Plates from which the Book of Mormon was allegedly translated were made from tumbaga instead of gold.