State officials have recovered the Narragansett runestone, a hunk of sandstone bearing unexplained carvings, which disappeared last year. Attorney General Peter Kilmartin’s office said Friday that the rock was retrieved after an individual came forward with information. The boulder-sized rock sat just offshore of North Kingstown until it was reported missing last year. The rock began attracting attention in the 1980s for markings that resemble ancient Norse runes. Claims that the runes are evidence of a visit by Vikings are unverified, although their origins are a mystery.