TUTORIAL
- How to identify fake trilobites
by
Dipl. Geol. Jens
Koppka, Heiko Sonntag & Horst Burkard
www.trilobiten.de,
www.trilobit.org/forum
-
copyright
2003
As trilobite
collectors and preparators visiting many fossil shows and fairs we have had
the chance to obtain some experience with fake trilobites. The
knowledge we have gained over so many years allows us to quickly identify
false material while it may be very difficult for others who are not so
familiar with how fake trilobites are made. Unfortunately the
trilobite market seems to be flooded with false stuff at the moment, the
“quality” of which is getting better continuously, making it even harder
to tell. We therefore, thought it a good idea to make our knowledge
available to others in a way easily understood.
We also have
to point out that there is no overseeing authority of control, as far as
trilobite (as we as ALL fossil) sales are concerned on the internet, in
shops or at shows, and no action taken against dealers who knowingly sell
false material (like exclusion from shows and/or legal action). This unwelcome
situation almost encourages certain dealers to take advantage and the honest
dealers are the ones who have to pay for it. Horst Burkard undertook
to investigate many of the false trilobites coming from Morocco, using one
of the most brutal methods available …. he took a saw! The results
of his little massacre were on display during the Hamburg Fossil Show in
2003 and we had a chance to talk to him and take photos. The following text
was originally written in German by Jens Koppka, photos taken by Heiko
Sonntag. Translation by Michael Kipping. www.trilobita.de
Historical
Aspects
Faking
trilobites is not a new business. Repairing, restoring, adding to or
plain faking of fossils is almost as old as the fossil trade itself.
The problem being, as with most areas of collecting, that money can be made
and sometimes has to be made due to lack of other options and wide-spread
poverty.
The famous
19th century trilobitologist BARRANDE, employed former quarry workers that where called “stone mens”
to search the areas near Prague for trilobite specimens.
Particularly interesting finds resulted in good money and some of those
“stone mens” could not help but fail their employer and produce false
trilobites in order to get more money for them. With the beginning of
the trilobite trade at the end of the 19th century, many of these faked
specimens found their way even into the collections of great museums around
Europe where they are on display even today as refreshing curiosities (Budik
& Turek, 2003).
A favored way
to fake trilobites was simply to assemble new specimens from parts,
originating at times not only in different specimens but even in different
genera, and thereby making the “trilobite” complete, resulting in higher
prices when sold. Some of these “rare species”, which had been
sold to museums and educational institutions, look quite grotesque in our
time. There was, for example, a trilobite assembled from the cephalon
of a Phacops, the pygidium being an Odontochile and the
thorax consisting of merely 4 segments. (SNAJDR, 1992). However, at
those times, the faked trilobites at least consisted of real parts.
They were created in a “make-one-out-of-two”-manner but the parts were
real. Fakes of this nature are created unto this very day, but the
availability of resins made it possible to fake entire trilobites by simply
casting them.
Following
sensational finds of large and bizarre trilobites in the Moroccan desert
near Alnif, Erfoud and Tabourikt over the last three decades, a whole
trilobite industry evolved. This happened in an area where education
was scarce and the availability of electricity and running water restricted.
Native Moroccans and nomads found a welcomed (if not their only) income in
searching for and preparing trilobites. Over the years, trilobites
have become an important economical factor in the poverty-stricken areas of
the High Atlas mountain range where the
Moroccan
trilobites are found.
According to
Burkard & BODE (2003), there are well-known manufacturers in Morocco
who produce fake trilobites or rather trilobite models. Fossil dealers
who go to Morocco to buy trilobites are well aware of that and know that
these trilobites are not real. Neither are these models sold to them
as real trilobites but reproductions. The cheating does not start
there, it starts when these reproductions are thrown onto the trilobite
market in masses and sold as the real stuff for little money. Faking
of this nature started in the 1980s due to increasing demand for giant Paradoxides
and lack of the real thing. In the beginning, the old
“make-one-out-of-many” was common, but very soon whole trilobites were
faked. It is verified that it was not the Moroccans who started to
fake trilobites but American as well as European dealers who inspired them
to do so. The American and European dealers then sold the fake
trilobites as the real thing. Meanwhile the faking has reached levels
that include almost any known Moroccan trilobite species and it is possible
that there is more false material floating around at this time than real!
But the
repairing, restoring or faking is not restricted to Morocco. It
applies as well to some of the
Russian
trilobites coming from
the St. Petersburg region, although the amount of faking is not comparable
to that in Morocco. It applies as well to some of the Russian trilobites
coming from the St. Petersburg region, that is also comparable to that in Morocco .
The reconstructions are usually restricted to replacing missing parts of the exoskeleton,
waxing and coloring of the carapace or the mounting of isolated trilobites onto matrix
other than the one it was found in. But also the building complete specimens from
pathials occur sometimes. I experienced this myself when
trying to prepare the hypostome of a Dysplanus from the Lower
Ordovician. The trilobite was completely real but mounted artificially onto
a piece of matrix from the Asery level. Most likely it was done
because a trilobite on a nice piece of matrix sells for a much higher price
than an isolated specimen. From a scientist’s point of view, it
looked as if this species from the Kunda level had still existed in the
younger Asery level, which is not the case.
It has to be said though, that the Russian preparators rarely play dirty.
The trilobites are real but in most cases (Asaphus, Illaenus)
are very quickly extruded from the matrix with high-powered blasters using
very aggressive media so that the exoskeleton gets an unnatural shine.
They look very nice when finished, but have most likely been polished and
waxed and thereby lost surface detail. Looking at more carefully
prepared specimens you will find the characteristic surface details, little
inconsistencies produced by nature but lost in specimens that have been
blasted too aggressively. The more rare spiny trilobites like Hoplolichas,
Boedaspis, Paraceraurus and so on are for the most part
very carefully and skillfully prepared and therefore, very expensive.
Fake
trilobites are known even from
Bolivia.
I have not had a chance yet to take a look at such material myself but we
have been assured that there are assembled trilobites on the market as well
as complete fakes made of plaster or resin including both positives and
negatives, so watch out!
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Some hints
as to identifying fake Moroccan trilobites
1. air
bubbles in matrix and exoskeleton as signs of resins.
If you
discover tiny holes in the matrix or the trilobite exoskeleton you can
assume you are dealing with a fake trilobite. These tiny holes, usually less
than 0,5 mm in diameter, are the results of bursting bubbles of air that
formed during the hardening process of the resin used to cast the trilobite.
(see Picture1).
Picture 1:
A) simple fake, a Drotops trilobite completely made of resin, the cast
trilobite then mounted onto the matrix, the tiny holes in the resin surface
can be easily seen. B) magnified view of part of the axis. C) air bubbles in
the matrix of a faked Dicranurus indicate that the trilobite including
underlying false matrix has been mounted onto a piece of real rock, the
resin shows an unnatural brown color, real matrix should be of a dark grey.
2.
differences in matrix color frequently with cast trilobites
If you find
different colors in the matrix of Devonian trilobites, for example a light
brown close to the trilobite while the rock, once you turn it over, is of a
dark grey, this indicates there may be trouble ahead. Usually the rock
is of an evenly dark grey (Hamar L’Aghdad), reddish or light yellow (Laatchana)
color. If there are differences in color as described and in addition
to that very extensive preparation marks on the surface (to hide tiny
holes), then both the trilobite and an underlying layer most likely were
cast and later mounted on some real piece of rock.
In Cambrian giant trilobites you can sometimes find color variations of the
matrix that may indicate that the specimen was assembled from different
individuals. Look for thin lines were parts may have been glued
together with their respective colors. Trilobites without tampering
should have an evenly level and colored matrix.
Picture 2:
complete fake of a spiny Moroccan trilobite, Dicranurus monstrosus.
The trilobite plus an underlying layer were cast from brown resin and then
mounted on top of real rock. The “trilobite” was then painted, the
surrounding areas covered with preparation marks. The saw proved
it! Notice the hole underneath the “trilobite” and the color
difference between the brown resin layer on top and the real rock beneath
which is grey. Photo taken by Sonntag, sawed up by Horst Burkard
3. crack line
in Devonian trilobites as an indication of authenticity
If you cannot
find any crack line in Devonian trilobites that can be followed on
throughout the surrounding matrix then be suspicious. These crack
lines are characteristic for authentic trilobites from the very hard rocks
of the Devonian of Morocco. It is hard to find a trilobite without
splitting it with your hammer. The absence of a crack line may be an
indication of a fake trilobite so take a close look.
4. color and
substance of the trilobite exoskeleton
The
exoskeleton of most Moroccan trilobites is of black, in some rare cases of
dark brown or olive color. Many faked trilobites show different colors,
often brownish, with an unnatural shine to it. Making careful use of
your front teeth, you can test the trilobite for authenticity. Fake
trilobites will feel “soft”, like plastics. This method is simple
and safe at the same time, because the nerves in your teeth are sensitive
enough to tell the difference without damaging the specimen. Authentic
trilobites are much harder than faked ones made of resin. Try it using
your toothbrush and some piece of rock. But please be careful, a
slight touch will do, don’t try and bite into it!
As far as
trilobites from the Ordovician and Cambrian of Morocco are concerned, their
exoskeleton has been replaced with hydrated iron oxides like limonite, the
color being a shade of brown or orange rather than yellow or black, as has
been seen in some faked trilobites.
Picture 3:
these trilobites are authentic specimens, for only if you know what real
trilobites look like will you be able to identify the faked ones. The
Paralejurus on the left shows the characteristic crack lines of a Devonian
trilobite (marked by arrows), the upper one clearly visible on the cephalon,
the lower one not so obvious. Top right: clearly visible terrace lines
on the pygidium of the Paralejurus. These lines will be missing in
faked trilobites or specimens that have been treated too aggressively with a
blaster. Notice the tiny white spots, they are preparation marks
resulting from direct hits with the tip of the prep needle but of course,
they will also be gone once a blaster has been used in the manner
described. Bottom right: the individual eye lenses of trilobites of
the order Phacopida are a sign of authenticity because they are (still) hard
to fake. It should be noticed, though, that schizochroal eyes are peculiar
to the Phacopina, which are abundant in the Devonian of Morocco but of
course there are other trilobites as well (Lichida, Harpetida, Proetida).
5.
morphological characteristics, surface details and trilobite eyes
The
exoskeletons of real trilobites very often show fine structures,
inconsistencies and ornamentations, there are terrace lines (see the Paralejurus
above), little knots, knobs and spines. Taking a close look at the
trilobites’ eyes will be helpful as, e.g., the Phacopina have
schizochroal eyes, the individual lenses clearly visible to the naked eye.
Faked trilobites usually lack these characteristic details … it is hard to
copy nature perfectly. Faked Phacopina usually have smooth
eye surfaces, because the production method of cast trilobites does not
allow for such details to be reproduced.
6. UV-lights
and solvents as tools to identify resin
If you are
not sure whether you are dealing with a fake trilobite a UV-light may be of
assistance. Resin reflects ultraviolet light and therefore starts
gleaming when exposed to a UV source. A real trilobite is mineralized,
it has the same reflection habits as the surrounding matrix. Be
careful, however, when testing waxed or finished trilobites like those
coming from Russia, they may start gleaming under UV light and still be
“real”. Waxing and finishing is a commonly used method to increase
contrast or conceal minor damages to the exoskeleton.
Moroccan trilobites sometimes are covered with an unidentifiable black
paste, both real specimens and faked ones. We use a solvent like
Aceton or Bindulin to remove such patinas from trilobites. Take a
paintbrush and confront your trilobite with the solvent and within seconds
the paste will come off, as do other artificial colorings. Use the
solvent on real trilobites to remove the paste and see what remains …..
perhaps not too much, if you are unlucky. If there are restored areas
they will appear white because the color came of.
7. The
ultimate and final solution – the saw!
If you are
still in doubt about the authenticity of your trilobite then saw it up with
an appropriate saw (diamond-covered blade). Is there is a hypostome
present? Bad luck - chances are you just sawed up a real trilobite!
is there a hollow area underneath the trilobite and resin has been used?
Then your trilobite was fake but it should not be necessary to saw up your
specimen unless you want to prove its lack of value 100%.
Picture 4:
a completely faked Burmeisterella, the hole underneath the cast trilobite
can be easily seen, the use of a shiny finish to pretend a real trilobite
exoskeleton is evident. This fake was 25 cm in length. Photograph taken by
Sonntag, specimen owned and sawed up by Burkard.
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Examples
of faked Moroccan trilobites
- Unnatural
trilobite assemblages
Frequently
seen at shows are the combinations of various faked trilobites on a single
plate. I call this a “faked assemblage” (see pic. 5). These
plates tend to be circular in shape, thin and slightly hollow. I have
even seen clocks mounted to the center, surrounded by cast trilobites.
There are simply no such assemblages in nature. This does not mean
there cannot be several authentic specimens on a single plate, it simply
means there are no such natural parties of different species that often do
not even appear in the same geological formation.
Picture 5:
completely faked trilobite assemblages, all made of resin with an underlying
layer and mounted onto real rock, casts identified as: Leonaspis,
Walliserops, Crotalocephalus, Paralejurus, and something unidentified on top
(left image),Odontochile, Psychopyge, Phacops and Scutellum (right image).
Photography: Sonntag, specimens owned and sawed up by Burkard.
- The
"Burmeisterella " - Fake Trilobites or Trilobites that do
not exist
Some of the
most impressive fakes coming from Morocco are the complete "Burmeisterellas"
(Picture 6). To the best of our knowledge, unto this day, no authentic
complete specimen of this kind has actually been found in Devonian of
Morocco. It has to be said that all complete specimens we saw so far
turned out to show manipulations, at least. Burmeisterella
belongs to the Homalonotidae, close relatives to the Calymenia.
The partial remains of these large trilobites are found isolated in the
Devonian of Morocco. There do not seem to be complete specimens.
They make for very impressive trilobites and it is no wonder that inventive
Moroccans took all the parts they could find, cephalons, pygidia, pleurae,
etc., and assembled them to form what they believed would represent a
complete specimen of this genera. They just took every rock that was
found to contain parts of these Burmeisterellas, extracted the
parts completely from the surrounding matrix and collected them until they
had everything they needed to assemble a trilobite. According to Mr.
Burkard, the Moroccans exchange missing parts among each other: "I
need pygidia of this spiny trilobite and I have pleurae of that species that
you are looking for, let's make a deal."
Picture 6:
The
"Homalonotida"- Fake. A: Spiny Burmeisterella sp.? (Spines are
actually tiny Orthoceras glued onto the exoskeleton, real trilobite parts
are assembled and fixed with resin onto a prepared piece of real matrix. B:
Smooth Burmeisterella sp.? Cephalon and pygidium of this trilobite consist
of real trilobite parts, the thorax section marked by the red lines is made
of resin. Both faked specimens are approximately 25 cm in length. Photos:
Sonntag, B: Photo from the collection of Burkard. P.S. In 2002 Heiko and I
saw these "trilobites" for the first time and were both fooled.
Once they
have all the parts they need - real parts but coming from various
individuals - they will take them and place them one by one onto a piece of
prepared matrix, most likely specially made from the Devonian of Morocco,
using resins and plaster. There seems to be a spiny and a non-spiny
type of Burmeisterella. The first one however, if it does
exist in nature at all, was in our case faked by gluing tiny
Orthoceras
(the tiny shells of a kind of
cephalopod)
onto the exoskeleton in order to mock real spines. We have been
assured by Mr. Burkard that these Orthoceras have been found in
certain places in such masses that they are used frequently now to mock
spines of all sorts, making it much easier to produce fakes. In former
times, the mock spines had to be made from plastics, it is much more
comfortable using the tiny Nautiloids. So once the
"trilobite" has been assembled, the Orthoceras are glued
onto the cephalon, thorax, pleurae and pygidium and there you go - a
fantastic looking trilobite, wow! There are, cases in which only the
cephalon and pygidium are real and the thorax is made of resin as can be
seen in Picture 6-B. The
quality of these fakes can be very good, at least the trilobites look very
impressive! Some of the less sophisticated fakes - mostly of the
smooth kind of Burmeisterella in a brownish color - often show
unnatural distances between the pleurae (see Picture 7-A), the matrix in
between looking carved. The first time we saw this it already looked
sort of suspicious to us but we could not be sure until we sawed the
sawed-up pieces (see Picture 7-C) of Mr. Burkard's during the Hamburg
Fair's special exhibition on faked trilobites in December of 2003.)
Picture 7:
more examples of faked Homalonotida from Morocco. A: the red stripes mark
the resin in between the assembled pleurae, the right side of the pygidium
was most likely broken off, so the right pleurae were shortened in order to
pretend that the trilobite was still partially buried inside the matrix. B:
cutting right through the "trilobite", the red lines and spots
marking areas made of resin, the whole thorax, the free cheeks and the
anterior border are faked and made of resin. C: a sawed up spiny Homalonotid,
the spines are actually tiny
Orthoceras,
real trilobite parts appear yellowish while the resin looks grey. Debris of
rock has been mixed with the plaster used to save material. All
photographs taken by Sonntag, trilobites belonging to and sawed up by
Burkard.
- Fakes
of giant Cambrian trilobites
The giant Paradoxidae
from the Cambrian of Morocco are well-known and sought-after trilobites
worldwide. It does not surprise that these trilobites have become the
subject of extensive faking activities. The demand is satisfied by
producing false material either assembled from isolated trilobite parts or
completely made of resin or plaster. These fakes now seem to represent
the major part of the Paradoxidae traded and it is not that easy
to acquire the real thing. At the same time, it has become more
and more difficult to identify fakes (see Picture 8-A), although there are
still some very bad ones around that can be easily told (see Picture 8-C),
faking is an art itself!
Picture 8:
All Paradoxidae that can be seen here are fake! A: Acadoparadoxides
briareus Geyer 1993: brown-yellowish painted cast trilobite, about 25
cm in length, fixed into an artificial mould using resins, the arrows
marking a crack where the cast and the rock did not completely glue
together, the circle marking an area where the artisan working on the cast
failed the natural symmetry of the pleurae, it is quite certain that fakes
of this nature have been sold in the past. B: Cambropallas telesto
GEYER 1993: The same disintegration between cast and matrix can be seen in
this image (red circle), the pleural tips have been created way too long and
tipped (should look like the pleurae to the left), the whole trilobite about
15 cms in length. C: very primitive fake of Cambropallas, perhaps
the rear section of the axis is real but everything else is made of resin or
plaster, the glabellar furrows carved into the cast, proportions inadequate
compared to the real thing. D: the cast has completely disintegrated from
the mould it was placed in. Photos taken by Sonntag, Photographs A, B, D:
collection Burkard.
How can you
tell fakes? For the most part, the trilobites are made of resin or
plaster using negatives of real Paradoxidae, painted and then fixed
into a mould dug into a real piece of Cambrian matrix. Because of the
inadequate gluing between the materials used, the cast very often, partially
disintegrates from the rock and tiny cracks appear along the
cast/matrix-line (see Picture 8, A-B) or the cast disintegrates from the
rock altogether and the whole construction falls apart (see Picture 8-D).
As far as the cast itself is concerned, the same criteria that is already
mentioned in the chapters on Devonian trilobites apply. The casts
often look very smooth and symmetric, preparation marks and at least smaller
damages that should be present in real fossils are missing. There are
neither cracks or missing areas to the exoskeleton, remains of matrix
between the pleurae or the characteristic features of the exoskeleton
surface (e. g. the small tubercles on the exoskeleton of Cambropallas
or terrace lines on the free cheeks of Acadoparadoxides
trilobites). The natural color of the Cambrian Paradoxidae
very often is being imitated by using a brown-yellowish paste that does not
exactly match the real thing. Many fake trilobites show a suspicious
shade of yellow. The original exoskeleton of Cambrian trilobites has
usually been replaced over time with hydrated iron oxides (often limonite)
of red and brown color or yellow and brown, therefore jet black Cambrian
trilobites have surely been the subject of manipulation, painted over to
cover restorations, etc, and to create a "better contrast".
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Evolution
in Moroccan fakes - from simple casts to imitations of matrix
The early
days of trilobite fakes saw Moroccans carving trilobites out of pieces of
rock, which sometimes led to very odd results due to the lack of
morphological knowledge to produce convincing fakes (see Picture 9-A).
In the beginning (and perhaps still today to fool tourists), not only
trilobites were reproduced but scorpions and even snakes including zig-zag
lines were carved out of and/or into the rock. I have seen huge wheels
of ammonites completely fake. Well, maybe the artisan had a good day
and turned the piece of rock he was sitting on into a nice huge ammonite -
surely he will find a buyer for it.
As already
stated, the early fakes of trilobites were very primitive, made of a little
plaster or resin and the details formed using a tool of sorts and before the
material hardened. At times, this resulted in fantasy trilobites with
large numbers of thorax segments or cephalons and pygidia that would not fit
and/or were morphologically incorrect. Perhaps the
"trilobites" were created out of memory or from bad sketches.
The problem, apart form the sometimes ridiculous morphology, was that the
border between cast material and real matrix could be easily told.
Because of that, the artisans very soon adopted the procedure to cover the
whole chunk of rock with a layer of resin or plaster mixed with crumbled
rock and perhaps a little color into which the cast trilobite is placed (see
Picture 9 B-D). The trilobite is made by casting resin into a
negative. The hardened imitation is then placed into the artificial
layer, and once the whole construction is hardened, the border line between
fake trilobite and fake matrix as well as the line between fake matrix and
real rock is covered by extensive preparation gash marks to deceive the
unwary eye and cover tiny holes resulting from bursting bubbles of gas in
the hardening material. However, these preparation marks are very
often way too irregular. After that, the whole creation is painted,
often failing to reproduce the right color shades. The whole process
of faking the trilobite takes two hours perhaps (excluding the hardening
process that can take several hours to complete). A real trilobite,
depending on the kind of trilobite and the skill of the artisan prepping it,
will take at least 5 hours or more to complete, perfectly prepared specimens
may have seen 100 hours or more.
Picture 9:
A:
fantasy trilobite pretending to be a Phacopida from the early times of
trilobite fakes (piece was acquired in 1983). B-D: good reproduction of
Odontochile from the Lower Devonian of Morocco, produced 20 years
later. Apart from the missing eye detail (lenses) the
"trilobite" is morphologically correct and detailed but being cast
and fixed onto a layer of resin or plaster on top of real rock. Photo B,
bottom right, clearly shows an area of disintegration of the artificial
layer from the matrix. Photos C and D show the smooth surface of the eyes,
eye detail is missing, there are no lenses as with authentic specimens.
Psychopyge
- beloved and frequently faked
This
impressive trilobite from the Lower Devonian deposits of Morocco with its
strange extension of the cephalon is very popular with collectors and
therefore frequently subject to manipulation and fakery. Authentic
specimens bear three rows of very fine spines (one row on the axis and one
row on each side at the borderline between pleurae and pleural spines).
The labor involved preparing these spines is very time-consuming and
difficult work and a specimen perfectly prepared will cost a small fortune
(4-digit sum in US dollars), but you will get fakes for a several hundred
dollars! So, if you are looking for a bargain on a spiny trilobite, be
very careful when coming across Psychopyge trilobites! A few
years ago, an acquaintance of ours very proudly presented one of these
specimens to us and was very disappointed when - after carefully
investigating the trilobite under magnification - we had to tell him that it
was fake. Because of its bizarre morphology, Psychopyge is
also very popular with the general public on websites, at shows and in
fossil shops, which may be one reason why this trilobite is frequently found
faked in numbers, as mentioned. Cast single pieces with fake or real
rock matrix have been selling for years.
When we have
a look at the faked Psychopyge in picture 10 below, what we notice
is not only the brownish color and the many tiny bubble holes in the resin
but the very crude preparation marks. You can tell a good preparator
by the way he "cleans up" his workplace, namely the matrix
surrounding the finished trilobite. A good preparator will try and
give beauty not only to the trilobite but to the matrix as well by evenly
roughening it and giving it a nice light color or by carefully blasting it
after which it becomes a nice grey. The procedure also increases
contrast between the fossil and the matrix. The intention to create
something really beautiful is not too common with the people faking
trilobites so keep your hands off stuff that does not look good or simply
seems "suspicious".
Picture 10:
not too good a fake of Psychopyge elegans from the Devonian deposits of
Morocco. Just another matrix imitation and a cast trilobite on top,
both the trilobite and the underlying matrix were made of resin. A: very
suspicious is the brownish-grey color of the trilobite (black would be
normal), the surface of the exoskeleton is rough and full of bubble holes.
B: magnified view of the cephalon - both eyes and glabella seem to have been
somewhat carelessly modeled. C: the resin pleurae have obviously been carved
a little, resulting in a sharp-looking appearance, again: note the bubble
holes! D. the tail spines seem to have been carved as well with some sharp
modeling tool, bubble holes again in both the "trilobite"
exoskeleton and the underlying "matrix". Photography: Sonntag (We
found this piece from a Moroccan dealer at a German fossil show).
Dicranurus
monstrosus - a frequently faked horned trilobite
This
trilobite has one of the most bizarre morphologies coming from the Lower
Devonian of Morocco. Remarkable are the two very prominent horns on
the occipital ring. The trilobite is rare and rather difficult to
prepare. At least you cannot prepare this trilobite with simple tools
as have been used in Morocco early on. The difficult preparation may
be one reason why there are so many fakes floating around, another being
that this trilobite usually represents the more expensive kind of fossil.
As already mentioned, the crude preparation marks indicate an old-style
Moroccan preparation and should already raise a red flag. In many
cases, the matrix (or resin with faked trilobites) in between the horns has
not been removed (see Pic. 11). If the matrix shows a light brown
color and the exoskeleton a shade of brown (straight black would be normal)
then chances are you are dealing with a fake specimen.
Like with the
other trilobites we discussed the fakes of Dicranurus mostly
consist of both the trilobite and a matrix layer being cast from resin or
plaster and then glued on top of a chunk of real matrix, the typical
"imitated-matrix-fake". Well-prepared GENUINE trilobites of
this species frequently show free-standing horns.
Picture 11:
A typical Dicranurus monstrosus fake, about 10 cm in length. A cast
trilobite and a cast layer of matrix glued onto a chunk of real matrix. 1:
frontal view of Dicranurus, clearly visible are the crude prep marks
pretending to be the real thing. 2: the pygidium under magnification.
Note the circled tiny holes resulting from bursting bubbles of gas during
the hardening process. 3: The pleurae have obviously been manipulated using
a sharp carving tool, the pleurae looking very sharp, real ones are circular
in shape. 4: cephalon under magnification: note the partially removed color
from the left horn to prove the fake and reveal the light color of the resin
used.
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Acanthopyge
- Advanced Faking!
During the
Hamburg Fossil Show, we came across a very well-done fake of Acanthopyge
(see Pic. 12) which is a relatively large Lichid trilobite from the Devonian
of Morocco (the specimen we are talking about was some 10 cm in length but
there are larger ones around). Complete specimens of this species are
rare and this fact made us look more closely. The dealer had a second
complete specimen which already raised a red flag (and several obvious fakes
of Psychopyge lying around). We were pretty sure that the
trilobite had been manipulated, so we decided not to buy, instead took out
our magnifying glasses and cameras and took a few shots of the specimen but
we were not able to tell right away what exactly was wrong with this
trilobite. It was not until we investigated the photographs more
closely and with various zoom levels on our laptops later on that we slowly
discovered the truth.
I had
convinced myself during the show that at least parts of the exoskeleton were
real, using the tip of my teeth to test the hardness of the shell. I
did this test on both the cephalon and the pygidium. But we had
noticed that the trilobite had been mounted onto the matrix (see Pic. 12 A),
particularly in the bottom right area the badly concealed line were the
parts were glued together was evident. The question was: Why should an
apparently real and complete specimen be mounted onto alien matrix?
Perhaps because it may have a better look then and reach a better price when
sold? I did not think so.
Picture 12:
Acanthopyge trilobite, assembled from parts of several trilobites
from the Devonian of Morocco. The parts are authentic but they
originate from different individuals or a disarticulated specimen. A: the
little arrows mark the line where the trilobite has been mounted onto the
matrix, clearly visible in the bottom right. Some of the pleural spines,
some of the pygidial spines and both genal spines are made of resin, the
head was slightly shifted to the left when mounted, the lower part of the
thorax lacks symmetry (mistake during assemblage). B: occipital ring
reconstructed using resin as is the right free cheek C: the ellipse marks
parts of the pleurae reconstructed using resin, the arrows marking areas
which indicate that the thorax may have been assembled from single isolated
pleural segments. D: the left spine on he pygidium is made of resin, tiny
holes in the matrix close (encircled) indicate where resin or plaster was
used to imitate matrix. Images: Sonntag
Taking a
closer look at the images taken during the show we soon came to the
conclusion that the genal spines (and parts of the free cheeks) as well as
the eyes (carved from matrix) were false. The pleurae are, for the
most part, authentic as are both the cephalon and pygidium. We are now
convinced that the trilobite was assembled from parts of several individuals
or perhaps disarticulated remains of a molt. All parts may have been
present but no longer in the right position or, as already mentioned, the
individual parts of the trilobite have been collected over time to finally
assemble this particular "complete" specimen of a rare trilobite.
We are facing the same trick that has already been used in the Burmeisterella
fake, perhaps
slightly altered. An authentic chunk of rock from the same level that
has contained the Lichid-parts with a mould dug into it and the
parts of the trilobite, carefully cleaned of any real matrix, reassembled on
top of a matrix imitation made of resin and plaster which was then glued
into the mould. Again, the resin being mixed with powdered rock
material and easily identified by the little holes resulting from the
bursting bubbles of gas during the hardening process (see Pic. 12-D).
It must have been tricky to isolate single pleural segments from their
matrix. It looks as if this effort was not always successful and that
parts of the pleural segments broke into pieces and therefore needed to be
restored. The first five segments do not seem to have been
artificially assembled, perhaps this part of the thorax was still present as
a whole. In the area of the pygidium, the borderline between authentic
rock and mounted resin can be easily seen, the artisans have taken more care
to conceal this line in the area of the cephalon. I have to admit that
the people faking this trilobite have made great efforts to produce “good”
quality. The question is “why”? Heiko told me, that he had
heard that the locality where the Acanthopyge was found was
running out of material. It seems the digging reached such an extent
that literally half the mountain is gone. In total, only a handful of
complete Acanthopyge
specimens seem to have been found, 40 specimens perhaps, that’s a pretty
small number for Moroccon trilobites. However, this may serve as an
explanation why people have invested so much time in fabricating trilobites
of this quality ….. for the simple reason that there are not any new
specimens to be found and since Acanthopyge trilobites reach high
prices on the market, it adds to the lure of making money with fake
trilobites.
Selenopletis
– Ordovician trilobites are not safe from being faked
Many
Ordovician trilobites of Morocco are found complete and well-preserved
within geodes (e.g. Flexicalymene and Asaphellus) so
there is little reason to fake THESE TYPES. It is a different matter
when it comes to spiny Ordovician trilobites like Selenopeltis
(Pic. 13), which is a typical representative of the Gondwana trilobite
fauna, found both in the Czech Republic as well as in England and
Morocco. In Morocco however, Selenopeltis is usually found
in very hard, fine grained, grey-white rock. The hardness of the rock
requires careful and skilled preparation and it is both difficult and
time-consuming to extract all the spines. It has to be assumed that
these trilobites cannot be extracted from the rock by simply splitting it as
with many other trilobites from the Ordovician because parts of the
exoskeleton very likely will remain stuck in the negative and have to be
prepared onto the positive later on. The difficulties in preparing,
the rare occurrence and the high value of these trilobites add to the lure
of fabricating. Horst Burkard has acquired a fake specimen of Selenopeltis.
The fake, however, is easy to tell. The trilobite’s exoskeleton is
of a brown color when it should be black (see Pic. 13-A). We are
dealing with a cast trilobite glued onto a chunk of rock. The
connection was not very stable so that the cast has already started to
disintegrate from the matrix. (see Pic. 13-B). The quality of the cast
is also very low because many morphological details got lost in the process,
e. g. on the glabella (see. Pic. 13-E). The length of the lower
pleural spines is incorrect, way too short and clearly visible to the eye
when compared to an authentic specimen. The artisan also failed to
produce the mild shine of a real calcified exoskeleton. The fake
trilobite has a rough surface while the real stuff is very smooth and shiny.
The sediment is of an equally bad quality.
Picture 13:
Selenopeltis sp. from the Middle Ordovician of Morocco (Caradoc). A,
D, F: authentic specimen, collection Burkard; B, C, E: faked Selenopeltis
trilobite, A: authentic specimen, about 15 cm in length, embedded in white
sediment, some of the pleurae seem to have already been broken off before
the trilobite was embedded. B: cast trilobite made of resin, cast is
disintegrating from the matrix that it was glued onto, pleural spines way
too short, lack of symmetry in the axis; C: magnified view of the area of
the pleurae and axis, the resin displays a rough surface; D: the same area
(but right side) with the authentic specimen shows black color and light
reflecting characteristics, the axis is not that well preserved and
therefore displays some rough spots; E: the head shield under magnification,
segmentation of the glabella not visible, glabellar lobes hardly to be seen;
F: the authentic specimen shows all morphological details. Both specimens:
collection Burkard, photos taken by Sonntag.
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Tips on collecting
trilobites
Beginners in trilobite
collecting, unless they start collecting themselves in the field, should get
in contact with reputable dealers in order not to get into trouble.
There is a series of dealers which over the years have earned a good
reputation as far as the quality of their goods is concerned. A good
dealer will give you advice and notify you of any repair or restoration.
But that should not prevent you from asking specific questions! On the
other hand, there may be cases in which even the dealer himself is not aware
of the fact that he has bought fake trilobites and is reselling them to
trusting customers. Therefore, no harm is done when you decide to have
a close look at a specimen, keeping in mind what you read in this article
and having a magnifying glass in hand. With doubtful cases at larger
shows, do not hesitate to contact the DMF people for guidance, they usually
offer ID-services. (DMF is the German Fossil Dealer's Association - note of
translator). (No service exists in the U.S.)
Reputable dealers usually
do not display at small local shows and festivities. The danger of
acquiring false specimens is very high there. Even at regular
specialized shows, there will be black sheep. We had the pleasure of
meeting many reputable Moroccan dealers at those shows but at the same time
many who also sold junk and fakes. Be careful when coming across
multiple-specimen-slabs, the shapes of which appear soft, the exoskeletons
rather dark grey or brown instead of straight black. Be extra careful
when the dealer is insisting on its authenticity, it’s “one-of-a-kind”
status and that he will sell it to you cheap anyway. (see. Pic. 14).
Picture 14:
slab of about 25 cm in diameter with obviously mounted specimens of Ceratarges
and Proetus, the circles mark color differences which indicate
badly concealed manipulation, the arrow bottom right indicates a brownish
area that may represent faked matrix. It is likely most specimens
displayed here are cast trilobites made of resin, but perhaps this time the
artisans have simply used authentic Proetus trilobites and badly
prepared Ceratarges and mounted them onto the slab to form this
particular piece. Photo taken by Sonntag.
At the beginning, I spoke
about restorations of trilobites and would like to be a bit more specific
about that. The question always is: what is justifiable restoration,
where does it end, where does the fake begin? Because of visual
reasons and sometimes because of higher revenue (that’s where the fake
starts), trilobites are being “restored”, small parts, a missing spine
or an eye are replaced using resin but resin should only be used in very
small quantities. The more resin is used, the less valuable the
trilobite is going to be. Replacing a whole free check in a trilobite
molt - then in my opinion the line has already been crossed. Minimal
restoration, just millimeters in size, may perhaps be regarded as ok but
that’s about it. In the end, most trilobites are found using a
hammer and in danger of the trilobite being damaged. That’s just the
way it is and cracks in the trilobites do not have to minimize its
value. Perfectly preserved trilobites without any cracks are very,
very rare.
Browsing trilobites for
sale with common sense, open eyes, a magnifying glass and a good portion of
suspicion is a good policy to escape fakes. Look at what the dealer is
selling. Does he sell lots of cheap and badly prepared Moroccan
trilobites (we do not even have a look at these specimens any longer because
there is hardly anything to be saved) or does he in general, sell high-value
preparations only? Get informed about the average sales prices of
well-prepared trilobites, e.g. using the internet. Try it by using a
search engine and a familiar genera and be reminded that
quality
has its price!
References:
BUDIL, P. & TUREK, V.
(2003): Trilobitenland Tschechien. – Offizieller Katalog der 40.
Mineralientage München, Turmalin und Trilobit:
94-99, 8 unn. Abb.; München.
Burkard, H. & BODE, R.
(2003): Trilobitenland Marokko. Keine Angst vor Fälschungen. –
Offizieller Katalog der 40. Mineralientage
München, Turmalin und Trilobit: 136-144, 22 unn. Abb., München.
Snajdr, M. (1990): Bohemian Trilobites. – 265 S.; Prag
BUDIL, P. & TUREK, V.
Permission by Trilobiten.de
(Original German version of the artikle :
http://www.trilobit.org/Content/fakes/tutorial_faelschungen.html)
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