[1] The formation has provided fossils of many mammals, birds, amphibians and reptiles, as well as mollusks and ostracods, and is considered one of the richest Early Eocene faunal assemblages of Europe.

The taeniodont, typically known as a North American order; Eurodon silveirinhensis and the ostracod Cypris silveirinhaensis have been named after the formation.

[2] The formation comprises fossiliferous lenticular calcitic conglomerates as well as laminated and cross bedded sands and brownish-red silts.

[1] The conglomerates are interpreted as crevasse-splay deposit in a alluvial plain environment, which eventually flooded and where bogs and possibly oxbows developed, crossed by channels depending on a river system that drained higher areas more north or eastwards.

The Silveirinha clay pit after which the formation is named was first discovered in 1977 by Rui Pena dos Reis of Coimbra University.