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PHOTO ABOVE AND TWO BELOW SHOW THE DETAIL OF THE BACK SIDE OF THIS SOLID, SEDIMENTARY FOSSIL-BEARING LAYER. MANY MULTIPLE TRILOBITE FOSSILS ARE COMPOSITES OF SEPARATELY DUG SPECIMENS AND GLUED TOGETHER, BEING ARTIFICIALLY ARRANGED. THE CONTRARY IS TRUE OF THIS EXTRAORDINARILY RARE PIECE. THE BACK OF THIS SEDIMENTARY ROCK LAYER SHOWS ONLY A FEW FRACTURES FROM EXTRACTION AND A NATURAL FORMERLY EXPOSED PARTIAL FACE ON THE UPPER PHOTO RIGHT SIDE OF THE SLAB AS INDICATED BY THE LIGHTER WEATHERED ROCK. THE DARKER REGION WAS COVERED WITH ANOTHER ROCK LAYER WHICH WAS SPLIT OFF WHEN THIS SPECIMEN WAS COLLECTED. REPAIRED FRACTURES MEET EXACTLY WITH ONLY A VERY FINE LINE OF JAGGED BREAK INDICATING THE SLAB WAS ALL ONE INTACT SLAB AND IS ORIGINAL WITH NO ADDITIONAL FOSSIL SLABS ADDED TO ARTIFICIALLY CREATE THIS MASS DEATH ASSEMBLAGE OF TRILOBITES. EVEN SMALL PIECES OF THE ORIGINAL SLAB THAT BECAME FRAGMENTED WERE RETAINED AND GLUED BACK TOGETHER AT A FEW FRACTURE JUNCTION POINTS.
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RARE MUSEUM GRADE NATURAL CONCENTRATION OF 18 SELENOPELTIS TRILOBITES ON VERY LARGE ORIGINAL SEDIMENTARY ROCK LAYER Ktaoua Formation - South Morocco ORDOVICIAN PERIOD: 488 - 443 million years ago Truly a museum grade display fossil slab of impressively large proportions, this is an amazing 100% NATURAL association of 18 complete and partial large Selenopeltis spiny trilobites on their original sedimentary fossil layer. Such a naturally-occurring concentration of these trilobites in well-preserved form is uncommon. Furthermore, the quality of the overall grouping as well as the intactness of the rock layer is something that is RARELY seen. If a museum wished to display a visually impacting specimen of exotic, extinct marine life from nearly a half a billion years ago, this piece would be one that public visitors would likely remember and be duly impressed by! Many multiple Moroccan fossil slabs are artificially created by gluing together partial and complete trilobites on a rock base to make an impressive grouping. Such fossils are NOT rare and of little scientific value compared to a specimen such as this where all trilobites died in this position as seen above and together in a layer. Some catastrophic event must have occurred to kill off so many of these at once. The evidence of this being an original and natural association of these trilobites is the fact that there are cracks running through the trilobites that correspond to the fractures seen on the back side of the slab. There is also lacking any epoxy joints where the trilobites meet the rock. Finally, the back side shows a 100% original rock slab a detailed in the photo text above. These above three photos of the back show the complete original sedimentary fossil-bearing rock layer with a lighter weathered portion and a darker split layer surface. Repairs of the rock butt up perfectly as they are the original pieces reassembled. Even small fragmentary pieces were saved and included in the repair. You can even see colored striated sedimentary formation lines in the slab on the back side. These reverse photos demonstrate the spectacular scientific quality of this piece from a perspective of natural features. The trilobites were prepared where they all were originally buried with NO FABRICATION or adding of parts missing to the trilobites or repositioning of the fossils. Where it was needed to expose a trilobite in a lower layer, this was done and if parts of the trilobites could not be saved to reveal portions of the rock or if they were only partial carapace fossils, this was left as it was found without fabricating complete trilobites out of partials. Again, from a scientific perspective, this is an EXTRAORDINARILY RARE specimen because it is natural and so well preserved with such a large concentration of these trilobites, some in enormous lengths. For the ultimate commercial or residential interior design application or for a public museum exhibit, this is an extremely rare and interesting very large fossil slab of the finest scientific grade showing a rare and visually intriguing AUTHENTIC AND ORIGINAL example of some of the earliest complex marine creatures on our planet.
Next to dinosaur fossils, trilobites command a dedicated and passionate following amongst both scientists and fossil collectors, alike. In a relatively short time-frame (scientifically speaking, of course), we have the emergence and subsequent extinction of these fascinating creatures. Still most baffling is the incredible diversity of sizes and features that made up the trilobite group. Many bizarre species co-existed with highly specialized body parts that defy the theories of evolution in their "sudden" emergence and diversity during the Early Cambrian Period in what is known as the 'Cambrian Explosion'. Trilobites were among the world's first arthropods, a phylum of hard-shelled creatures with multiple body segments and jointed legs (although the legs, antennae and other finer structures of trilobites only very rarely are preserved). They constitute an extinct class of arthropods, Trilobita, that is comprised of over 15,000 known species. It has been reported that every year, four to five new species are discovered in the Atlas and Anti-Atlas Mountain regions in Morocco, alone! This desolate northern fringe of the Sahara Desert was once covered by a prehistoric ocean and its fossil deposits can be considered the world's richest and most diverse source of these ancient sea creatures. Trilobites are the single most diverse group of extinct organisms that ever existed, period! The smallest known trilobite is just three millimeters long, while the largest type grew to a length of 70 centimeters (over two feet long!). The most common fossil of trilobites is the mineralized dorsal exoskeleton of the creature. This is found in partial form from molting (shedding the shell as it grows) or in complete form when the animal was buried and died intact. The soft parts of the underside are rarely preserved. The name 'TRILOBITE' means 'three lobed" and is derived from the fact these animals had bodies featuring three longitudinal lobes, not lateral (head, body, tail) as is often thought. The lateral division of three parts is shared by many arthropods, not just trilobites. Considerable study has been done on trilobites as a whole organism. Even more fascinating though, is the research done on a microscopic level with regards to trilobite morphology. Radiographs have captured incredible detail of complete and fully articulated antennae and underparts like legs and gills, preserved in the host rock of some fossilized specimens. Perhaps the most impressive and classic feature of trilobites that comes to mind is the eyes. Microscopic studies of trilobite eye structures have also revealed marvelous adaptation and very high degrees of specialization in vision. It seems that the more we learn about trilobites, the unfolding of their mystery is stranger than fiction. Certainly we gain a greater appreciation with each new discovery of these strange and highly advanced but now extinct 'butterflies of the ancient seas'. RARE HIGHLY CONCENTRATED DEATH ASSEMBLAGE OF VERY LARGE AND SUPERBLY PRESERVED SPECIMENS OF THIS RARE SPINY TRILOBITE A TRUE MUSEUM PIECE! 31" x 25.5" overall with a slab of 2" average thickness, trilobites range in length from 8" to 4.5" in lengths $19500 TRX-025 Actual Item - One Only |
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