(PCM) The Visby Lenses were found on the Swedish island province of Gotland
What:
Several lens-shaped pieces of quartz of varying size found in a Viking grave, dating back to the 10th century. read more
(PCM) The Visby Lenses were found on the Swedish island province of Gotland
What:
Several lens-shaped pieces of quartz of varying size found in a Viking grave, dating back to the 10th century. read more
