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An early specimen of ‘AMMONITES Walcotii’ and Sowerby’s ‘Mineral Conchology’

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A version of this article is published in Depositsmag . A fascinating aspect of palaeontology is the history of early descriptions and the process of assigning and revising the scientific names of fossils. A recently discovered nineteenth century ammonite specimen discussed here provides a vivid illustration of the sometimes tortuous process and can be connected with several illustrious naturalists and geologists from the seventeenth to nineteenth centuries. Geology in the first quarter of the nineteenth century The first quarter of the nineteenth century was a particularly important time in the evolution of geological thinking. The first long stratigraphic sections were being published, the Geological Society was founded in 1807, the first nationwide geological map was published in 1815, and detailed investigations were underway across the country. A correspondent in the Philosophical Magazine (‘A Constant Reader’ 1815) promoted the work of James Sowerby and mentioned contemporary...
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Traditional Art of Gabon: Brass Adornments of the Fang

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" In a little bay we pass we see eight native women, Fans clearly, by their bright brown faces, and their loads of brass bracelets and armlets, intent on breaking up a stockaded fish-trap. "  Mary Kingsley, 1895, Travels in West Africa.  Mary Kingsley speculated that these eight ladies were wearing anklets, but couldn't see them since they were standing in the water. Living in Gabon in the 1990s, I bought one such bracelet (below), with beautiful incised decoration, from an elderly Fang lady who had a battered mask with her and an aged leather pouch containing this bracelet, an arrowhead-shaped piece of iron and a very simple thin brass bangle. A richly decorated copper alloy bracelet I purchased from an elderly Fang lady in Gabon in the 1990s (RS.AF2). A similar example is illustrated in Grébert (1932) reproduced in Grébert et al. (2003) ' Another brass ornament (see below) has a distinctive and symmetrical pattern of ornament, with a central rectangular field enclos...
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The Viking Borre-style Gripping Beast Pendants

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A decade ago, I suggested that a 10th century gripping beast pendant found widely across the Viking world (Campbell 2013) may represent a bound shapeshifter (reminiscent of Loki's fate as recounted in the "Lokasenna" of the Poetic Edda), perhaps functioning as an amulet for the 'containment of chaos' . The design of the pendant features a highly contorted quadruped with forward facing head and a ribbon body connecting thorax with hindquarters in lateral view. Two of the animal's limbs are bound to an encircling rim and a third grips the creature's own ribbon body. The circling ring is ornamented with four fanged beast heads in facing pairs on each side of the pendant. Two small paws reach over the long ears of the lower two beast heads to grasp on to the encircling ring. Details of the ornament on the  fore- and hind-quarters vary between examples and a distinctive variant from the Lake Ilmen region of Russia lacks the beast heads around the rim of the pen...
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The 'Ragnarok Stone' at Skipwith

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Skipwith (North Yorkshire), immediately to the north of Skipworth Common, where tradition held that the few remaining Norse warriors from the failed 1066 invasion had gathered and buried their dead (at 'Danes' Graves'), is the site of an ancient church containing a fascinating early medieval low relief sculpture. St. Helen's Church has been renovated several times over the past millennium, but still preserves a pre-conquest structure in the form of the tower with its original Anglo-Saxon windows. The ancient tower of Saint Helen's Church at Skipwith, showing original Anglo-Saxon windows Set low inside the tower wall (in the modern vestiary) is an ancient image carved into a stone. It's thought to be a re-used Roman stone (magnesian limestone) with a pre-conquest carved scene, later included at the base of the church tower wall. The timing of the block's incorporation in the wall is unknown, the carving not having been noticed until 1866 following lowering of...
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Jurassic Fossil Cephalopods Preserving Aragonite Shells

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Aragonite is a common mineral in the skeletons of marine organisms (Cusack & Freer 2008), but is not typically well preserved in the fossil record due to its tendency to recrystallise as its more stable polymorph calcite. However, certain circumstances can enhance the preservation of the original aragonite, including reducing conditions (Jordan et al. 2015), low temperatures (associated with limited burial depths), and burial in impermeable sediments (Hall 1967, Vendrasco et al. 2018).  Four Middle to Lower Jurassic examples of preservation of aragonite shells, consisting of two belemnoids and two ammonites, are illustrated here below. Consideration of these examples also leads to a discussion on preservation of soft parts in fossil cephalopods. Middle Jurassic Oxford Clay of Christian Malford The Middle Jurassic of Christian Malford (Wiltshire) is celebrated for the exceptionally preserved fauna it contains (Pearce 1842, Wilby et al. 2004, 2008). J. Chaning Pearce read his pap...
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