The agates of the Scotts Quarry are situated in the fossil remnants of marine animals.The here shown bivalved shell, that is split up crosswise is belonging to the Niagara escarpment strata.
Agates from the Niagara Escarpment represent the northernmost agates in the USA, which originate from sedimentary rocks. The Niagara Escarpment forms an elongated geological stage trough Ontario, Michigan, Wisconsin and Illinois, as well as trough a part of Canada. Their oldest rocks originate from the silurian age. The highest layer is a dolomitical limestone.