Concretions are plentiful in the mudstones of central Wales. Some sites produce distinctive concretions, which can be particular to that site. This concretion is from a small roadside quarry just north of Dolfor, Nr.Newtown, Mid Wales. I have collected three similar specimens from the site. Each one has distinctive marks all around the base, which are compatible with the sedimentary layers from which they came. The age of the rock is Silurian. There is another type of concretion from this quarry which is very distinctive, and this will be placed on this site in the near future. For definitive concretion information, see Tony Thorp's article in the Silurian magazine No. 1 which can be found on this website.