Discovery on the Mureș River
In 1974, workers digging on the banks of the Mureș River near Aiud, Romania, discovered three objects buried 10 meters (about 33 feet) in the sand. Two of the items were easily identified as the fossilized bones of a mastodon, an extinct relative of the elephant that died out at least 11,000 years ago. The third object, however, was a metallic, wedge-shaped block that was difficult to explain.
This object, weighing approximately 2.3 kilograms (5 pounds), was sent to the Archaeological Institute of Cluj-Napoca for analysis. It measures about 20 centimeters long, 12.5 centimeters wide, and 7 centimeters thick. The object's placement in the same geological layer as Pleistocene-era fossils suggested it was of a similar ancient origin, a proposition that would soon become highly problematic.
An Impossible Composition
Initial analysis of the artifact, conducted at an institute in Măgurele, produced a startling result. The object is an alloy composed of 12 different metals, with the primary component being aluminum at 89%. The other elements include copper (6.2%), silicon (2.84%), zinc (1.81%), and smaller amounts of lead, tin, zirconium, cadmium, nickel, cobalt, bismuth, and silver.
This composition is the mystery. Aluminum is not found in a pure state in nature and requires an industrial process for extraction from bauxite ore. This process, which needs temperatures of nearly 1,000 degrees Celsius, was not developed until the 1880s. The discovery of a manufactured aluminum object in a geological context suggesting an age of 11,000 years or more contradicts the known history of metallurgy.
The object is coated in a thick layer of aluminum oxide, over one millimeter thick. Some analyses of this patina suggest an age of at least 300 to 400 years, which, while not as old as the mastodon bones, still predates the invention of aluminum production by more than a century. Skeptical investigators propose a more recent origin. One prominent theory suggests the object is a tooth from a modern excavator bucket, possibly from mining operations or even WWII-era German aircraft. This type of aluminum alloy is similar to modern duralumin, which oxidizes quickly. The exact provenance and function of the object remain unresolved.