Sunstone (medieval)

For the mineral gemstone, see Sunstone. For other uses, see Sunstone (disambiguation).
Iceland spar, possibly the medieval sunstone used to locate the Sun in the sky when clouds obstruct it from view

The sunstone (Icelandic: sólarsteinn) is a type of mineral attested in several 13th–14th-century written sources in Iceland, one of which describes its use to locate the Sun in a completely overcast sky. Sunstones are also mentioned in the inventories of several churches and one monastery in 14th–15th-century Iceland and Germany.

A theory exists that the sunstone had polarizing attributes and was used as a navigational instrument by seafarers in the Viking Age.[1] A stone found in 2002 off Alderney, in the wreck of a 16th-century warship, may lend evidence of the existence of sunstones as navigational devices.[2]

  1. ^ Cite error: The named reference thorkild was invoked but never defined (see the help page).
  2. ^ Satter, Raphael (March 8, 2013). "Researchers: We may have found a fabled sunstone". Yahoo! News. Associated Press.