Baltic amber is the best known of all the inclusion-bearing ambers and is often washed up on the shores around the Baltic Sea. The Upper Blue Earth Member of the Prussian Formation is the main source of this amber, although it also occurs in beds above and below. The age of Baltic amber has been a subject of controversy for many years, but it is important to know what its most likely age is when studying the evolution of different animal and plant groups trapped in the amber, particularly taxa used in phylogenetic trees. A review of the different dating techniques confirms that dinoflagellate cyst biostratigraphy is the best method for dating the amber-bearing beds. Here we correlate the published dinocyst species records with the zonation schemes in the Geologic Time Scale 2020 to provide more accurate and up-to-date dating of these beds. The Prussian Formation is late Eocene (Priabonian) in age, 37.7–34 million years old, and the Upper Blue Earth Member is mid-Priabonian, 36–35 million years old. Amber from the Upper Blue Earth is considered to be the same age and, given that it is concentrated towards the base of the member, an age of 36 Ma can be used in phylogenetic trees. Baltic amber of unknown provenance is probably Priabonian in age.

The macrofossil record of the lower Palaeozoic Stavelot-Venn Inlier is revised. This inlier is the largest of the four inliers of the Ardenne Allochthon in southern Belgium and northern France, and it extends from southeastern Belgium into western Germany. The thick succession of mostly siliciclastic rocks has been traditionally assigned to the lower Cambrian to Middle Ordovician, but macrofossils are extremely rare and the microfossil (acritarch) records need revision. The presence of the ichnogenus Oldhamia indicates an early/middle Cambrian age for the lower (but not lowest) part of the succession. The graptolites from the Rhabdinopora fauna clearly point out the presence of the Tremadocian (Lower Ordovician) strata; they are locally associated with small linguliformean brachiopods (e.g., Broeggeria, Lingulella). The present revision, based on examination of the Belgian material, indicates that none of the trilobite, phyllocarid and sponge records in the literature can be confirmed. From all macrofossils mentioned in the literature, only few linguliformean brachiopod levels can be confirmed in the (? middle–upper) Cambrian and in the Lower Ordovician. The alleged bivalve from the Cambrian of the French part of the Rocroi Inlier is reillustrated.