This item was found near a former water hole adjacent to an old way. Directly in the water hole, now a swamp, early modern horse shoes were founds. The circular plate has a diameter of 10 cm. The hole has a diameter of some 3 cm. The item was quite deep, ca. 30-35 cm. In the neighbour hole axis nails were found at a similar depth.
These find circumstances suggest an use in connection with horses, carriages, and travel. Though, the hole is so clearly off-center that I do not think it was part of a mechanical construction. I was unable to find any such item in literature or internet forums. The only similar item were round iron ingots used as currency in early medieval times in the Baltic region. Since this item was found in southern Germany that seems rather far-fetched though.
Material is non ferrous, probably copper alloy, though no green patina is visible. At the place of the right eye a small item of is attached, probably also made from copper alloy.
Several pieces of a grey porous stone called tuff. These four pieces were found on the forest surface near a place where Roman items have been found. Interestingly, two items each fit together. When brought to the museum they said a Roman origin cannot be excluded but seems unlikely. Maybe these items once served as some sort of decoration to a building.
(C) Thorsten Straub www.metal-detecting.de 2006-2011.