They are usually rough-hewn slabs or boulders, and in a few cases well-shaped crosses, bearing lettered and symbolic inscriptions of a rude sort and ornamental designs resembling those found on Celtic scriptures of the Gospels. Their lettered inscriptions are in Latin, Ogam or Scandinavian and Anglicanrunes, while some are uninscribed. Sculptured stones are usually found near ancient ecclesiastical sites, and their date is approximately fixed according to the character of the ornamentation. Some of these stones date as late as the 11th century. The Pictish stones from Scotland are particularly remarkable for their elaborate decoration and for certain symbolic characters to which as yet no satisfactory interpretation has been found.