A number of enigmatic carved stone balls have been found at the site and some are on display in the museum. Similar objects have been found throughout northern Scotland. The spiral ornamentation on some of these "balls" has been stylistically linked to objects found in the Boyne Valley in Ireland. Similar symbols have been found carved into stone lintels and bed posts. These symbols, sometimes referred to as "runic writings", have been subjected to controversial translations. For example, Castleden suggested that "colons" found punctuating vertical and diagonal symbols may represent separations between words.