TUTORIAL
- How to identify fake trilobites - defect version
by Dipl. Geol. Jens Koppka, Heiko
Sonntag & Horst Burkhard (© 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.
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 what
he called “rock men” to search the areas near
Prague for trilobite specimens. Particularly interesting finds
resulted in good money and some of those “rock men”
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 BURKHARD & 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. The reconstructions
are usually restricted to replacing missing parts of the exoskeleton,
fixing broken-off eyes and spines (every once in a while a
whole pygidium may be replaced), waxing and coloring of the
carapace or the mounting of isolated trilobites onto matrix
other than the one it was found in. 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!
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).
![](sonntag/abb1.jpg)
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.
![](sonntag/abb2.jpg)
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 Burkhard
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.
![](sonntag/abb3.jpg)
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%.
![](sonntag/abb4.jpg)
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 Burkhard.
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.
![](sonntag/abb5.jpg)
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 Burkhard.
- 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. Burkhard, 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."
![](sonntag/abb6.jpg)
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 Burkhard. 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. Burkhard
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. Burkhard's during the Hamburg
Fair's special exhibition on faked trilobites in December
of 2003.)
![](sonntag/abb7.jpg)
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 Burkhard.
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!
![](sonntag/abb8.jpg)
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
Burkhard.
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".
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.
![](sonntag/abb9.jpg)
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".
![](sonntag/abb10.jpg)
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.
![](sonntag/abb11.jpg)
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.
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.
![](sonntag/abb12.jpg)
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 Burkhard
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.
![](sonntag/abb13.jpg)
Picture
13: Selenopeltis sp. from the Middle Ordovician of Morocco
(Caradoc). A, D, F: authentic specimen, collection Burkhard;
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
Burkhard, photos taken by Sonntag.
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).
![](sonntag/abb14.jpg)
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: