Fossil identification
7. Dinosaur fossils
Other popular collectible fossils include dinosaur
claws and teeth – one
may think such may be more safely purchased as genuine, however
unfortunately this is not necessarily the case.
Certain dinosaur species are prone to compositing, heavy restoration – of
particular note are the brittle teeth of the huge Moroccan dinosaur Spinosaurus
aegypticus.
Whilst there is not one complete skeleton anywhere worldwide for
this species, teeth are frequently discovered and readily available
for a dinosaur hungry market.
8. Permineralization
A common form of fossilization is permineralization, which occurs
when the pores of plant materials, bones, and shells are impregnated
by mineral matter from the ground, lakes, or oceans. Sometimes
the wood fibres and cellulose dissolve and are replaced by minerals,
and at other times the mineral substance of the fossils will completely
dissolve and other minerals replace them. Common minerals that
form this kind of fossil are calcite, iron, and silica.
The fossils take the original shape of the tissue or organism
as the pores of the organic tissues are filled with minerals, or
the organic matter is replaced with minerals. However, the composition
of the fossils will be different and they will be heavier.
Permineralization is not as robust as (for instance) North American
counterparts with the teeth virtually always excavated broken requiring
repair – this in itself is not an issue, but with the brittle
enamel and dentine often too broken for adequate repair, all too
often one whole tooth is manufactured from two.
The joint is then usually filled with sand, impregnated with glue
and presented as a genuine original example.
Some very basic composition and repair is commonly seen with Spinosaur
teeth 25% to 40% comprising glue and sand with tooth size being
easily increased by artificially extending the root (often covered
with matrix).
9. Don't get the hump !
Moroccan artisans may create Spinosaur bones from camel bones
(both extant and extinct) – even claws may be carved and
shaped (including replication of blood grooves and nutrient pores) – with
genuine Spinosaur claws attracting high prices, the profit to be
made from carving mammalian bone can be considerable.
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