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Moroccon trilobites, an interesting story
Despite the fact that almost all kinds fossils are falsified, trilobites (especially Moroccan) deserve special attention. These fossils are faked on a large scale. They are copied, glued together ??and repaired. Sometimes even completely new species of trilobites are manufactured.
First something about the preparation of trilobites. Most species of Moroccan trilobites are found in very hard limestone in the Atlas Mountains. The result is that such an animal is extremely difficult to prepare. This is done on the street with a 'nail' that is used to extract the fossil from the stone by scratching. This is therefore rightly called trilobites slaughter. Because there is much damage by this way of preparation, they try to cover up the damage. The trilobite is often treated with putty, and then covered with a thick layer of black paint. Original Moroccan trilobites are not black, but brown, olive green or sometimes a combination of colors. You can imagine that this "repair" is only acceptable to a certain level.
How do I distinguish real from fake?
As I mentioned are the most real (Moroccan) trilobites are hidden deep in the stone. To find it, the stone is cracked and the trilobite broken. Therefore, you almost can not avoid that prepared trilobites often have a fracture. If this fracture cuts across everything (stone and trilopbite) it is not that bad. This is a sign that the trilobite and the matrix are original.
Always check the bottom of the stone. This gives information whether parts of trilobites have been mixed together, or that original parts are glued together (described above). Especially with the "trilobite-pizzas" you can clearly see the divisions between the pieces on the bottom. Note also the scratch traces of preparation. These are very often used to hide differences in color of the stone (real) and putty (fake). At a transition there is more scratching, observe this. Also, often you can see a (tiny) color difference in 'stone color'. Look the animal in the eye. Some orders have distinctive facet eyes, a detail which is difficult to imitate. Especially the holochroal eyes, i.e. in the species Scabriscutellum sp., are finely faceted and virtually impossible to forge. Note that this only says something about the eyes and possibly the cephalon. Other specific features of a trilobite help you in your research. If you know that a certain "phacopide" trilobite has 12 ribs and the species of offer has 16, there is something wrong. Also pay attention to symmetry. If something appears not natural (symmetric) formed, there is reason to further investigate. Finally, look for air bubbles. Fake parts that are made ??of a filler, pften showing residual air bubbles.
How can I determine authenticity experimentally?
Here some "test methods" to determine whether a trilobite is real. When buying trilobites is handy to take a little bottle of acetone and some cotton swabs. With this you can test in two seconds wether the trilobite is painted as you swab turns black. Keep in mind that black paint may be painted again with clearcoat, you have to brush a little longer. But first ask the seller of course. If the trilobite is real, nothing will happen and the acetone has no effect on the fossil. In fact, sometimes prepared pieces get an acetone bath for a final clean. Also tapwater can be useful. Plastered parts can repel the water more than genuine parts. Therefore, water droplets on it will behave differently and you can expose fake parts. The last regular method is "piercing with a hot needle". This is not always accurate because some modern putty is used which is properly heat resistant and will not melt directly.
More radical methods are using a burner on sawing the trilobite in half. With the first you have to be careful because you can damage the real parts, but the fake parts will first disappear. Do this outside because it stinks and it smokes! With sawing you can see if it is a total fake it glued to a real piece of stone.
You will understand that it is not easy to determine whether or not a trilobite fossil is authentic. We hope this will help you. When in doubt, you can always post your question on our Forum. Good luck!
Do you have additional information for this article? Please contact the Fossiel.net Team.