Here is a completely articulated Dalmanitina socialis from the Czech Letná Formation. The trilobite shows a good contrast and nice carapace surface details as well. And with 76 mm does has this trilobite also a good size.
Location:
Beroun, Barrandian area, Czech Republic
Size trilobite:
about 76 mm long
Age:
Middle Ordovician, Llandeilo, Letná Formation (About 464 mill. Years old)