Belemnite Fossils showing hues opal colours are rare to be opalised and found in deserts south Australian opal fields.
Belemnite is a prehistoric squid like creature that is estimated
to be over 100 million years old.
The harder parts of this creature are calcium carbonate and
this is left after the jelly part decays and sometimes opal may form as it
replaces the carbonate
Most opalised belemnites have little of blue colours and its
rare to find multi fire colour in these specimens.
These specimens are found in cooper pedy south Australia and
the Adelaide Museum has a magnificent 72.64ct part of a belemnite specimen that
has been valued at One million dollars