Updated: Dec 20, 2019
Finest detail, top quality prepared trilobites, prepared in-detail by experts in Morocco or in EU, USA..., are mostly authentic and natural - usually just cracks glued where the rock was split or minor restoraton to missing parts. In detail prepared trilobites! All trilobites sold in trilobiti.com are 100% authentic and if restored, restoration disclosed exactly, with step by step preparation photos of each specimen also always available. What about the rest?
On the other hand, often seen cheaply sold massacred Moroccan trilobite specimens, sold by many resellers online or at fossil shows, usually have "issues". Some species are more often fake than other, but it could be concluded that fakes of Moroccan trilobites are generally not problematic for serious trilobite collectors and are easily examined, so not confusing for science, nor collectors, except for beginners! Price is never a proof of authenticity, but you usually get what you pay for.
Although often described with superlatives as "rare", "superb", "fantastico", "in perfetto stato", "nice" in shops online... Are in reality: common, butchered, destroyed, fake, heavily restored and partial remains... And often not cheap at all, often not even cheap compared to better quality! All usually offered by your typical ebay listing and non-professional resellers!
For example! How a real Dicranurus trilobite looks:
And a total 100% fake Dicranurus from non-professional resellers:
Spines or hornes prepared flying are not a sign of fakery, but in most cases of massacred quick prepared trilobites, be careful!
1. rule: If the preparator did not preserve the finest details (check the eyes, tubercles, pores, etc. etc. - all fine skin details of each specific specie) and the spines are prepared flying, chances are: composition or total fake...
2. rule: Check the matrix and cracks running through the trilobite. All devonian trilobites are found splitting matrix and parts often need to be glued together.
3. rule: Random scratches all around the trilobite on the matrix are not a sign of fakery, nor proof of authenticity. Scratches like that are sometimes added to hide signs of fakery, but can also just mean preparator didn't spend time to landscape the matrix. See how nicely the matrix is shaped in 2. photo above and 3. photo below - total fakes and no scratches!