This is a rich Czech Agnostid plate with the species Peronopsis integra from the middle Cambrian Jince Fm.
There are three specimens of Peronopsis integra preserved as Positive and 5 pieces are preserved as negative or external mould. The largest Peronopsis mesures about 6 mm in length. This is a unusual dense accumulation of Agnostid trilobites for the Jince site.

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