![green epidote crystal val malenco valtellina italy green epidote crystal val malenco valtellina italy](https://www.mineralfossil.com/wp-content/gallery/macro/thumbs/thumbs_epidoto-sissone.jpg)
![vesuvianite val malenco valtellina italy vesuvianite val malenco valtellina italy](https://www.mineralfossil.com/wp-content/gallery/macro/thumbs/thumbs_vesuviana-val-lanterna-3.jpg)
![vesuvianite val malenco valtellina italy vesuvianite val malenco valtellina italy](https://www.mineralfossil.com/wp-content/gallery/macro/thumbs/thumbs_vesuviana-val-lanterna.jpg)
![geode calcedonio brasil (2).JPG geode calcedonio brasil (2).JPG](https://www.mineralfossil.com/wp-content/gallery/south-america/thumbs/thumbs_geode-calcedonio-brasil-2.jpg)
![geode calcedonio brasil.JPG geode calcedonio brasil.JPG](https://www.mineralfossil.com/wp-content/gallery/south-america/thumbs/thumbs_geode-calcedonio-brasil.jpg)
![magnetite brasil.JPG magnetite brasil.JPG](https://www.mineralfossil.com/wp-content/gallery/south-america/thumbs/thumbs_magnetite-brasil.jpg)
![quartz japanese geminate brasil.JPG quartz japanese geminate brasil.JPG](https://www.mineralfossil.com/wp-content/gallery/south-america/thumbs/thumbs_quartz-japanese-geminate-brasil.jpg)
![azurite morocco.JPG azurite morocco.JPG](https://www.mineralfossil.com/wp-content/gallery/africa/thumbs/thumbs_azurite-morocco-2.jpg)
![calcite morocco.JPG calcite morocco.JPG](https://www.mineralfossil.com/wp-content/gallery/africa/thumbs/thumbs_calcite-morocco.jpg)
![carollite.JPG carollite.JPG](https://www.mineralfossil.com/wp-content/gallery/africa/thumbs/thumbs_carollite.jpg)
![celestine madagascar.JPG celestine madagascar.JPG](https://www.mineralfossil.com/wp-content/gallery/africa/thumbs/thumbs_celestine-madagascar.jpg)
![cerussite barite morocco.JPG cerussite barite morocco.JPG](https://www.mineralfossil.com/wp-content/gallery/africa/thumbs/thumbs_cerussite-barite-morocco.jpg)
![malachite Democratic Republic of the Congo (formerly Zaire) Lukuni Mine in Katanga Province.JPG malachite Democratic Republic of the Congo (formerly Zaire) Lukuni Mine in Katanga Province.JPG](https://www.mineralfossil.com/wp-content/gallery/africa/thumbs/thumbs_malachite-democratic-republic-of-the-congo-formerly-zaire-lukuni-mine-in-katanga-province.jpg)
![vanadinite morocco.JPG vanadinite morocco.JPG](https://www.mineralfossil.com/wp-content/gallery/africa/thumbs/thumbs_vanadinite-morocco.jpg)
![almandine gilgit pakistan.JPG almandine gilgit pakistan.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_almandine-gilgit-pakistan.jpg)
![fluorite china.JPG fluorite china.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_fluorite-china.jpg)
![fluorite india.JPG fluorite india.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_fluorite-india.jpg)
![hematite rose on quartz china.JPG hematite rose on quartz china.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_hematite-rose-on-quartz-china.jpg)
![lapislazzuli afganistan.JPG lapislazzuli afganistan.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_lapislazzuli-afganistan.jpg)
![quartz epidote china.JPG quartz epidote china.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_quartz-epidote-china.jpg)
![topaz pakistan.JPG topaz pakistan.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_topaz-pakistan.jpg)
![topaz quartz pakistan.JPG topaz quartz pakistan.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_topaz-quartz-pakistan.jpg)
![tormaline pakistan.JPG tormaline pakistan.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_tormaline-pakistan.jpg)
![zircone pakistan.JPG zircone pakistan.JPG](https://www.mineralfossil.com/wp-content/gallery/asia/thumbs/thumbs_zircone-pakistan.jpg)
![analcime sardegna,Italy.JPG analcime sardegna,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_analcime-sardegnaitaly.jpg)
![andradite garnet isola d'elba,Italy.JPG andradite garnet isola d'elba,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_andradite-garnet-isola-delbaitaly.jpg)
![aragonite spagna.JPG aragonite spagna.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_aragonite-spain.jpg)
![calcite italy.JPG calcite italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_calcite-italy.jpg)
![calcite valtellina,Italy (2).JPG calcite valtellina,Italy (2).JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_calcite-valtellinaitaly-2.jpg)
![calcite valtellina,Italy (4).JPG calcite valtellina,Italy (4).JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_calcite-valtellinaitaly-4.jpg)
![calcite valtellina,Italy.JPG calcite valtellina,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_calcite-valtellinaitaly.jpg)
![epidote valmalenco,Italy.JPG epidote valmalenco,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_epidote-valmalencoitaly.jpg)
![grossularia liguria,Italy.JPG grossularia liguria,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_grossularia-liguriaitaly.jpg)
![hessonite adamello,Italy.JPG hessonite adamello,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_hessonite-adamelloitaly.jpg)
![orthoclase quartz elba island,Italy.JPG orthoclase quartz elba island,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_orthoclase-quartz-elba-islanditaly.jpg)
![pyromorphite sardegna,Italy.JPG pyromorphite sardegna,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_pyromorphite-sardegnaitaly.jpg)
![quartz emilia romagna,Italy.JPG quartz emilia romagna,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_quartz-emilia-romagnaitaly.jpg)
![quartz formazza,Italy.JPG quartz formazza,Italy.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_quartz-formazzaitaly.jpg)
![quartz rodocrosite romania.JPG quartz rodocrosite romania.JPG](https://www.mineralfossil.com/wp-content/gallery/europe/thumbs/thumbs_quartz-rodocrosite-romania.jpg)
![apatite messico.JPG apatite messico.JPG](https://www.mineralfossil.com/wp-content/gallery/north-america/thumbs/thumbs_apatite-messico.jpg)
Part of my job is to provide service teaching for the University of Leiden. The university lacks a geology department, but my colleagues and I provide tuition in stratigraphy and palaeontology for life science students at the undergraduate and masters degree level. One of my favourite practical classes is a building stones tour of a part of Leiden that is rich in Mississippian (Lower Carboniferous) limestones, which are packed with fossils. These have been used for facing stones, external stairs and paving slabs. Many have been in place for some hundreds of years and many have been etched by slow solution by rainwater as a result. Common fossils include crinoid columnals, tabulate and rugose corals, brachiopods, and molluscs (Donovan, 2016; van Ruiten and Donovan, in review). These are most commonly seen in two dimensions and random sections, a different view of life to what the life scientists are usually accustomed.
One group of fossils in these rocks were a mystery until recently, but we now know they are sections through rostroconchs (Donovan and Madern, 2016, p. 349), an extinct group of Palaeozoic molluscs. Rostroconchs were formerly considered to be an ancient group of bivalves and they are certainly bivalve-like in appearance, but lack an articulation of interlocking teeth and a ligament. That is, the shell is a univalve, a one-piece structure. I had only seen the sections of rostroconchs in building stones in Leiden. It was therefore gratifying, shortly after publication of these fossils, to receive an email from Jelle Reumer recording them from building stones in Middelburg, elsewhere in the Netherlands.
This brings me to the Hoofddorp rostroconch, also in Mississippian limestone. Unlike the buildings in Leiden discussed above, the specimen from Hoofddorp is from a recent development, in an area that was a farmer’s field when I first moved there in 2001. The site (Figs. 1 and 2A) is southwest of Hoofddorp railway station, just one stop from Schiphol International Airport. The site is a long reflecting pool (Fig. 2A), in the centre of an area of office buildings sandwiched between two roads that parallel the Zuid Tangent bus lane to the northeast (the roads are not shown in full in Fig. 1). The specimen (Fig. 2B) was found in the limestones edging the pool, on the left in Fig. 2A, and closer to the end furthest from the station.
That this specimen is a rostroconch is best demonstrated by comparing it with a complete shell (Fig. 3). Fig. 3 demonstrates the gross similarity to a bivalve. The section illustrated in Fig. 2B is close to those illustrated by Donovan and Madern (2016, fig. 1). Finding this specimen, less than two kilometres walk from my home, was like bumping into an old friend unexpectedly.
This leads me to a pertinent comment and a complimentary question. I will not be surprised if any or all of you recognise rostroconchs in your local building stones. Good luck. I feel that I have been a little dense in only recognising them now. But this leads to my second comment – what other ‘unidentifiable’ fossils are there in building stones in your local area? I am confident that someone in the Deposits ‘brains trust’ will be able to shed light on its true affinity.
Amler, M.R.W. & Rogalla, N.S. 2004. History and nomenclature of the Conocardioidea (Mollusca: Rostroconchia). Paläontologische Zeitschrift, 78: 307—322.
Anon. 1885-1890. Meyers Konservations – Lexikon: eine Encyklopädie des allgemeinen Wissens, 4. Bibliographisches Institut, Leipzig.
Donovan, S.K. 2014. Urban geology: A sunny Sunday in Hoofddorp. Deposits, 38: 8-10.
Donovan, S.K. 2016. A mollusc-coral interaction in a paving slab, Leiden, the Netherlands. Bulletin of the Mizunami Fossil Museum, 42: 45-46.
Donovan, S.K. & Madern, P.A. 2016. Rostroconchs in Leiden. Swiss Journal of Palaeontology, 135: 349-352.
Ruiten, D.M. van & Donovan, S.K. (in review with the Bulletin of the Mizunami Fossil Museum). Provenance, systematics and palaeoecology of Mississippian (Lower Carboniferous) corals (subclasses Rugosa, Tabulata) preserved in an urban environment, Leiden, the Netherlands. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen.
Buy Fossils, Crystals, Tools
Subscribe to Deposits
Join Fossil Hunts
UK Fossil Locations
Filed under: fossils, geology Tagged: Brachiopods, coral, corals, crinoid columnals, Fossil, fossils, geologists, geology, Limestone, limestones, Lower Carboniferous, molluscs, Rocks, rugose, sand, slabs, Stones, tabulate, University of Leiden, Urban Geology
Deposits Magazine