The Tucson artifacts, sometimes called the Tucson Lead Crosses, Tucson Crosses, Silverbell Road artifacts, or Silverbell artifacts, were thirty-one lead objects that Charles E. Manier and his family found in 1924 near Picture Rocks, Arizona which were initially sometimes thought to be created by early Mediterranean civilizations that had crossed the Atlantic in the first century, but were later determined to be a hoax.
The find comprised thirty-one lead objects consisting of crosses, swords, and religious/ceremonial paraphernalia, most of which contained Hebrew or Latin engraved inscriptions, pictures of temples, leaders' portraits, angels, and a dinosaur (inscribed on the lead blade of a sword). One contained the phrase "Calalus, the unknown land" which was used by believers as the name of the settlement. The objects also have Roman numerals ranging from 790 to 900 inscribed on them which were sometimes interpreted to represent the date of their creation because the numerals were followed by the letters AD. The site contains no other artifacts, no pottery sherds, no broken glass, no human or animal remains, and no sign of hearths or housing.
On September 13, 1924 Charles Manier and his father stopped to examine some old lime kilns while driving northwest of Tucson on Silverbell Road. Manier saw an object protruding about 2 inches (5.1 cm) from the soil. He dug it out, revealing that the object was a 20 inches (51 cm)-long lead cross which weighed 64 pounds (29 kg). Between 1924 and 1930 additional objects were extracted from the caliche, a layer of soil in which the soil particles have been cemented together by lime. Caliche often takes a long period of time to form, but it can be made and placed around an article in a short period of time, according to a report written by James Quinlan, a retired Tucson geologist who had worked for the U.S. Geological Survey. Quinlan also concluded that it would be easy to bury articles in the soft, silt material and associated caliche in the lime kiln where the objects were found at the margin of prior trenches. The objects were believed, by their discoverer and main supporters, to be of a Roman Judeo-Christian colony existing in what is now known as Arizona between 790–900 AD. No other find has been formally established as placing any Roman colony in the area, nor anywhere else in North America.
In November 1924, Manier brought his friend Thomas Bent to the site and Bent was quickly convinced of the authenticity of the discovery. Upon finding the land was not owned, he immediately set up residence on the land in order to homestead the property. Bent felt there was money to be made in further excavating the site.