By Paul Rincon
reporter, BBC News
skulls were made with tools not
available to Pre-Columbian cultures
Two of the best known
crystal skulls - artefacts once thought to be
the work of ancient American civilisations -
are modern fakes, a scientific study shows.
skulls are the focus of the story in the latest
Indiana Jones film.
experts say examples held at the British Museum
in London and the Smithsonian Institution in
Washington DC are anything but genuine.
results show the skulls were made using tools
not available to the ancient Aztecs or Mayans.
say the work, which is published in the Journal
of Archaeological Science, should end decades of
speculation over the origins of these
it casts serious doubt over the authenticity of
other crystal skulls held in collections around
team including Margaret Sax, from the British
Museum in London, and Professor Ian Freestone,
from Cardiff University, used sophisticated
techniques to work out how the two skulls had
"There are about a dozen or more of these crystal
skulls. Except for the British Museum skull and
one in Paris, they seem to have entered public
awareness since the 60s, with the interest in
quartz and the New Age movement," Professor
Freestone told BBC News.
does appear that people have been making them
since then. Some of them are quite good, but
some of them look like they were produced with a
Black & Decker in someone's garage."
added: "There seems to be the assumption that if
it is roughly worked, it is more likely to have
been made by a traditional society. That's
untrue of course, because people were quite
sophisticated. They might not have had modern
tools, but they did a good job."
researchers used an electron microscope to show
that the skulls were probably shaped using a
spinning disc-shaped tool made from copper or
another suitable metal.
craftsman added an abrasive to the wheel,
allowing the crystal to be worked more easily.
"rotary wheel" technology was almost certainly
not used by pre-Columbian peoples. Instead,
analysis of genuine Aztec and Mixtec artefacts
show they were crafted using tools made from
stone and wood.
British Museum skull was worked with a harsh
abrasive such as corundum or diamond. But X-ray
diffraction analysis showed a different
material, called carborundum, was used on the
artefact in the Smithsonian.
is a synthetic abrasive which only came into use
in the 20th Century: "The suggestion is that it
was made in the 1950s or later," said Professor
made the skulls is still a mystery. But, in the
case of the British Museum object, some point
the finger of suspicion at a 19th Century French
antiquities dealer called Eugene Boban.
assume that he bought it from, or had it made
from [craftsmen] somewhere in Europe," said
Professor Freestone, a former deputy keeper of
science and conservation at the British Museum.
documents suggest Mr Boban was involved in
selling at least two of the known crystal skulls
- the one held in London and another in Paris.
London skull was probably manufactured no more
than a decade before being offered up for sale.
the findings, a spokeswoman for the British
Museum said the artefact would remain on
permanent display to the public.
skull held by the Smithsonian was donated to the
museum anonymously in 1992, along with a note
saying it had been bought in Mexico in 1960.
is known of its history before that date, but
like the British object, it was probably
manufactured shortly before being purchased.
researchers were not able to determine where the
quartz used in the skulls was quarried. But
locations with suitably large deposits include
Brazil, Madagascar and, possibly, the Alps.
Freestone said the work did not prove all
crystal skulls were fakes, but it did cast doubt
on the authenticity of other examples: "None of
them have a good archaeological provenance and
most appeared suspiciously in the last decades
of the 20th Century. So we have to be
sceptical," he explained.
findings are likely to be a disappointment to
enthusiasts and collectors; the skulls have
become a part of popular culture, appearing in
numerous films and novels.