Description: Objects such as the one pictured above, and others, were discovered in viking villages dating to the 11th or 12th century. They were originally assumed to be ornaments. It was not until Karl-Heinz Wilms recognized the objects for what they were when he saw them in a Munich Museum. It is assumed that the vikings did not actually produce them but were made in Eastern Europe.
Mainstream Theory: These lenses were used for burning out wounds to prevent infection, light fires or as a magnifier for craftsmen. It is also believed that the lenses were made out of trial and error as the mathmatics needed to formulate the curvature of the lens had not yet been invented.
Alternative Theory: It has been noted that the quality of these lenses has not been duplicated until the 1950s. It is possible that these ancient people possessed the technology to create these lenses for use in telescopes.