The fields around Tiefenthal are a finding-location for agates and jaspers. They occur very seldom in pliocene gravelbeds. The gravel was transported by rivers from agate-bearing rocks from northern regions such as rhine-hessia. The evidence for this source are identically pseudomorphic structures after thin tabular crystallized carbonates. In the rhine-hessian area these pseudomorphic formations are called “Scolecite-Agates”.