PREPARATION TECHNIQUE OF
Before discussing replica
fossils from this source, it is important to understand how the genuine
specimens are prepared and conserved. Since the oil shales from Messel
are fragile and difficult to stabilize in the conservation of the fossils
found there, the most common technique for extracting and presenting these
fossils is by embedding the fossil in plastic resin on one side for a stable
backing. When the fossil is discovered in the field, resin is mixed
and poured over the exposed layer. The entire fossil with its
reinforced resin backing is then removed from the ground and brought back to
the lab where it is flipped over and prepared from the rock side which was
the former layer facing down. The preparation is done very carefully
with manual tools and in some cases, light air abrasives. The
surrounding rock is removed to expose the layer holding the fossil and if
done carefully, soft body tissue and other delicate features can be found
preserved intact. The resin is either colored or left natural and the
fossil is stabilized with a clear preservant to prevent damage to its
fragile features now that they are fully exposed.
OF FRAUDULENT MESSEL FOSSILS:
some special warnings that apply to acquiring Messel fossils. There
are three types of fossils that sometimes appear on the market from this
deposit that should be avoided due to their lack of value and authenticity.
Since the real fossils are prepared in resin, it is easy to create fakes or
fossils made from the rock negatives where no real fossil substance exists.
These are worthless casts and it is important to be able to identify the
difference. The following Messel fossils are to be avoided and are
nothing more than copies of the real thing. One key factor to
determining if the fossil is genuine is to look for crisp detail of the
skeleton or soft body tissue under magnification. Sometimes, the
organic preserved remains retain a variation of colors. AVOID DEALER
INVENTORIES WHERE ALL THEIR MESSEL FOSSILS OF THE SAME TYPE OF ANIMAL LOOK
THE SAME COLOR. They are probably not real.
fossils that have had all of their fossil material removed by improper lab
preparation leaving only the plastic resin impression and not any real
fossilized remains in the resin slab. The substance is accidentally
fully removed and then the fossil portion is colored to disguise the resin.
Messel fossils that are pure resin positive impressions of the original
negative rock layer, not the real fossil. In other words, when the
rock is split and the fossil is exposed, if you were to pour resin into the
negative impression rock slab that split off, you can make an
effective-looking fossil that is nothing more than a copy of the real one
found on the other slab. Unscrupulous collectors did this when it was
possible for the public to access the pit so these "negative side" Messel
fossils are out there and surface on the market from time to time. The
fossil region is colored to disguise the resin.
Messel fossils that are pure resin copies made from a rubber mold of a
genuine fossil. Silicone will retain the finest detail and since the
original fossil is embedded in resin, it is very easy to make a copy in
resin, as well. The fossil region is colored to disguise the resin.