The floor of the chamber is covered with a deposit of mud. The tomb is locally considered to be a holy well and offerings of coins, some quite recent, medals, broken glass, etc., lie on the lower roofstone. The interior of the chamber is littered with broken glass.
From p128 in ‘Survey of the Megalithic Tombs of Ireland, vol 1 – County Clare’ by Ruaidhri de Valera and Sean O Nuallain (1961).
In an article called ‘A Folklore Survey of County Clare‘ in Folklore v22, 1911, it says, “The mud of the dolmen or “well” of Tobergrania at Ballycroum cured sore or short-sighted eyes.”