Archaeology For Mystery Writers

Since the end of WW II, a number of scientific tests used in archaeology for dating and the discovery of fakes and forgeries can be useful for mystery writers.

The most famous of these is Radiocarbon dating. Carbon has two stable isotopes, C12 and C13, and an unstable isotope, C14, produced by cosmic ray impact on Nitrogen14 in the upper air. In 1949, Willard Libby at the University of Chicago, developed Radiocarbon dating, based on the ratio of the stable carbon atom, C12 to the unstable carbon isotope, C14, testing it against wood from an ancient Egyptian royal trade of known age.

Every living thing ingests carbon in the form of CO2 during its lifetime in order to stay alive. At death, the amount of stable carbon in the organism remains the same, but the unstable isotope, C14, begins to disintegrate at a steady rate, which had a half-life, Libby estimated, of 556860 years. Half-life method that in 5568 years, half of the C14 will be gone, and in another 5568 years, half of that half will be gone, etc., etc. The represents a standard deviation, which method that there are two chances out of three that the date falls within the 120-year range.

Are you with me so far?

Libby was wrong about the half-life. In 1962, the half-life was recalculated at 5730 years. But, because so many dates had already been published, published dates nevertheless used Libby’s half-life, and raw dates were published as BP xxxx yyy, with BP meaning not Before Present, but Before Physics, or 1950, when Libby first published his research. Dates were then recalculated using the new half-life.

Are you nevertheless with me?

Soon it was discovered that the production of C14 in the air is not continued, but varies with changes in the earth’s magnetic field, and is also affected by temperature changes, volcanism, and the introduction of CO2 into the air from industrialization. In order to correct for this, Radiocarbon dates were calibrated using reliable known dates, such as tree-rings, at first using Bristle-cone Pines, the oldest living trees, and then other material, such as thorough sea cores, lake hydroelectricity varves, coral samples and cave deposits. These are plotted on a curve, but there are wiggles in the curve, so a single Radiocarbon date could give several calendar dates.

nevertheless with me? Give up? Perhaps the most reliable method is to ask someone at the lab what the date really is.

There are other lab techniques that archaeologists use to discover date and place of manufacture, and uncover fakes, such as other radiometric techniques, neutron activation, thermo-luminescence, obsidian hydration, and others, but trust me, we won’t get into them now.

One of the earliest and most famous instances of the use of more progressive scientific techniques is the exposure of the Piltdown forgery.

After acceptance of Darwin’s theory of evolution by the scientific community, archaeologists searched everywhere for a ‘missing link’, conceived as a flawed creature, half-way between an ape and a human–early, dull-witted, half erect–and unable to cope with the modern industrial world of the nineteenth century.

Lo and behold, he was found in England, early jaw and all, near a hedgerow in Piltdown in East Sussex in 1912, in the gravel pit of an ancient river place.

In 1912, Charles Dawson, a solicitor and archaeology aficionado, brought particles of a thick human skull, fossilized teeth of extinct species of elephant and hippopotamus, and some crude flint tools that he had recovered from the gravel pit to the Keeper of Geology at the Natural History Museum in London. All were coated with a chocolate brown patina, as would be expected if the material had been buried for a long time.

Excavation of the site, sponsored by the Natural History Museum, revealed a break up of an ape-like jawbone with two worn teeth, more fossilized ancient animal teeth from the early Ice Age, some flint tools, and a carved, pointed bone tool, all with the identical brown patina.

Sir Arthur Smith Woodward, Keeper of Geology, presented this evidence for what he called Eoanthropius, the Dawn Man, at the meeting of the Geological Society of London in December. With a skull similar to modern man, but smaller, and the jaw of a chimpanzee, at last the missing link had been found.

There were some skeptics, but they were quieted in 1915, when Dawson, forging a head, found another skull break up and a molar tooth in the same gravel beds two miles from the original excavation.

As time went on, and more evidence of ancient hominids was uncovered, Piltdown Man began to be regarded as an secluded anomaly, if not an outright forgery.

Bit by bit, the forgery was exposed, starting with the teeth. The size of the roots of the teeth and the flat use on the teeth in the apelike jaw were more human than apelike. New x-rays of the jaw from a different angle revealed longer roots on the teeth, like those of apes. Using new technology, the use on the teeth were reexamined, this time under a Scanning Electron Microscope. The teeth had been filed to imitate characteristically human use.

A new technique for dating fossils, fluorine examination, based on the fact that over time, buried bone absorbs fluorine from the soil, was applied to the jaw, the brain case, and the animal teeth in 1953. Results of new tests indicated that the fossilized ancient animal teeth, the jaw, and the cranium were from different time periods, and from different burial sites. The cranium was from a Neolithic cemetery, the jaw from a modern orangutan, the fossilized ice-age animal teeth had different geographic origins and dated to from different glaciations.

All the evidence from the Piltdown gravels had the same dark brown patina. When Dawson died, his wife donated the apparatus from his scientific laboratory to the British Museum. Among these implements was the pot used to dye the Piltdown finds to give them their brown patina.

One interesting side effect of exposure of Piltdown man is the field day it granted Creationists, not only presenting them with the opportunity to challenge authentic Paleolithic finds, but also inspiring them to create hoaxes of their own.

There may be others.

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