This is a nice grouping of Upper Cambrian trilobites. They are Modocia weeksensis and Cedaria minor (center) from the Weeks Formation of Utah. There are three Modocia and two Cedaria on the plate. The trilobites display well on the very large block of matrix. This is an unusual assemblage of two different Upper Cambrian trilobites.
Note: These specimens were obtained legally. However, normally it is illegal to sell fossils from the Weeks Formation and other BLM land.