The initial state
Back side without any signs of a root
Side view with root found
The finished specimen
Das Endergebnis nach 17-stündiger Präparation
The Upper Cretaceous deposits in the Coesfeld area are widely known among german collectors. Among other things, well-preserved and impressive fossils of sponges stand out from the fossil record and fascinate with their shape and detailed surface structures. Especially the “sun sponges” are very popular, due to their imposing umbrellas. This piece is such a “sun sponge”, a representative of the genus Coeloptychium. The top of the umbrella has already been roughly exposed by the finder.
The rock is chalky-marly and soft and can therefore be worked very well. Particular care was taken along the rim of the umbrella because it is very thin and fragile. During fine preparation using air abrasives, the reticular structure had to be worked out gently, as it can be damaged very quickly. Initially, no root was visible around the stone. However, the root could be found only a few millimeters deeper in the rock. The stem lies slightly drifted under the umbrella, the underside of which was exposed about half.
Fossils: Coeloptychium sp.
Locality: Coesfeld (Germany)
Formation: Upper Cretaceous, Campanian
Diameter of the umbrella: 9 cm (3.5 inches)
Work required: 9 hours
Collection: Meik Ackermann