Fossils in glacial erratics from Urk added to geological collections Museum Schokland

Museum Schokland recently received a collection of fossils in glacial erratics found on Urk by Klaas and Lub Post. Over the past few decades, the collection has been held by several different institutions. It is of considerable scientific value and forms an exceptional addition to Museum Schokland’s geological collections.

Wandering fossils in glacial erratics

The brothers Klaas and Lub Post assembled an extensive collection of fossils in glacial erratics on the former island of Urk. The specimens were found at various locations on and around the former island. In 1992, following contact with Harry Huisman, the collection was donated to the Groningen Natural History Museum. Curator Harry Huisman recognised its scientific importance: the specimens had been collected within a single, clearly defined area and included a number of exceptional and rare fossils.

Unfortunately, a difficult period followed for natural history museums, and the Groningen Natural History Museum was no exception. The collection was transferred to the University of Groningen. From the university, it subsequently moved to the Hunebed Centre in Borger. The Hunebed Centre then informed representatives in Urk and Schokland about the collection of fossils in glacial erratics from Urk. Last year, Museum Schokland finally received the collection, returning the fossils to the familiar reclaimed seabed of the former Zuiderzee.

Museum Schokland’s rock collections

Museum Schokland holds extensive rock collections. Their foundations were laid by the well-known amateur geologists Pieter van der Lijn, Bernard Boelens and Wytze Tjeerd Hellinga. Geology courses continue to be organised at the museum to this day.

Over the years, the geological collection has continued to grow through donations, purchases and bequests. Recent additions include the rock collection of geologist J. G. Zandstra (2012), a fossil collection donated by the heirs of Mr Van Houtum (2014), and the collection of Geertje and Ernst Kleis (2022).

Museums such as the Hunebed Centre and Museum Schokland are committed to preserving this scientific heritage. The collection assembled by the Post brothers is a particularly valuable part of that endeavour.

Issue 1 of Conglomeraat (2026) included an article by Klaas and Lub Post, Harry Huisman and Henk Kloosterman entitled ‘There and Back Again: The Journey of a Collection of Fossils in Glacial Erratics’. The article provides a detailed account of the history of the collection. It also explores the history of Museum Schokland’s rock collections in greater depth.