at a phenomenal intensity of heat and pressure for a sufficiently long period of time. As the primordial fluid oozes over the first cell of silicon dioxide, the cell starts to replicate itself, laying down its complex crystalline structure one atom at a time. Every cell in the crystal repeats the same pattern. Each cell is a tiny little crystal in and of itself, and each cell repeats the same pattern as the one before. In this way the crystal builds up a complex three-dimensional network structure, known as a ‘crystal lattice’, with absolute geometric regularity, where every cell is exactly symmetrical and precisely repeated throughout the whole. And so little by little, over the years, a piece of pure, transparent natural quartz crystal comes into being. In its natural state it is highly angular in shape, always with six sides, tapering at either end to a fine point.
Of course, not every piece of natural quartz crystal is perfect. Impurities can creep in, traces of iron or aluminium or any number of other substances can get trapped in the network. Such traces of other elements show up as discoloration, aluminium for example turning the crystal smoky grey, known as ‘smoky quartz’, or iron adding a tint of pink, known as ‘rose quartz’, to name but two. High levels of radioactivity can also affect growth and cause discoloration. Only if there is no radio-activity and there are no other trace elements in the area is a totally pure and transparent crystal formed.
Quartz, however, is one of the most common naturally occurring materials. As Jack told us, current estimates are that around 80 per cent of the Earth’s crust contains quartz. But much of this is too full of impurities or too small to be of any practical use, other than as sand. And, whilst some of the less pure varieties of quartz are still beautiful, they are of relatively little use to the electronics industry. In fact a problem for the industry has been that large and pure pieces of natural quartz are actually very rare.
Recently this problem has been solved to some extent by the manufacture, or rather growth, of man-made or synthetic quartz. The first experiments in manufacturing or growing synthetic quartz began in 1851, but it was not until the latter part of the twentieth century that the technique was sufficiently perfected for manufactured quartz to be of practical use in electronics. In fact at the time that the tests on the crystal skull were performed at Hewlett-Packard, carefully selected natural quartz was still the main source of crystal for electronic devices, but since then scientists have become so successful at growing their own quartz that synthetic quartz has now all but completely replaced natural quartz as the essential ingredient for most electronic equipment.
The point about manufactured quartz is that the purity and size of the crystal can be absolutely guaranteed. But this is not to say that the process no longer requires the help of Mother Nature. On the contrary, it is only possible to manufacture quartz by growing it from natural pieces. What the scientists do is to speed up a process that would naturally take an eternity, so that it now only takes a matter of weeks. This is done by artificially creating the optimum environment for growth. In a vast ‘autoclave’, a highly sophisticated type of furnace, natural pieces of quartz scraps or ‘lascas’ are dissolved in water at highly elevated temperature and pressure. But the essential ingredient is still a natural piece of high quality quartz; without it the process cannot even begin. This carefully selected piece of natural crystal is simply suspended in the autoclave and the rest of the process is left to nature itself. The surrounding fluid quite simply grows onto the original crystal and the results are removed from the autoclave, or harvested, when the resulting crystals reach the required size. But these new crystals, even over generations and generations of man-made manufacture, can only ever be as pure as the original piece of natural quartz crystal supplied by Mother Earth.
Given all the different types of material that look exactly the same to the naked eye as natural quartz, the first task for the Hewlett-Packard scientists was to determine exactly what the crystal skull was really made of.
In one of the tests the skull was submersed in a glass chamber containing Benzyl alcohol of exactly the same density and refractive index as pure quartz. As the skull was lowered into the tank it seemed to disappear (see plate 36). This proved that it was made of the most incredibly pure type of quartz. But not only was it pure, it was also natural. Polarized light was directed at the skull in its chamber and vague shadows or ‘veils’ then appeared, which showed that the skull was of natural origin. These shadows, tiny variations in the growth pattern of the crystal, somewhat akin to the rings on a tree, are removed in the precisely controlled environment of manufactured quartz. So the skull was not made from any type of plastic or glass, nor was it made from modern synthetic crystal. It was definitely natural rock crystal supplied by the Earth.
The presence of the veils also revealed something else quite remarkable about the crystal skull. Given its size, unusually large for a natural piece of quartz, some had suspected that the skull had been made from several pieces of crystal carefully pieced together. But the polarized light test proved beyond doubt not only that the main cranium was made from only one piece of crystal, but also that the detachable jaw-bone was carved from exactly the same piece of rock. At some stage the crystal skull had been one solid block of rock crystal.
The investigating team was absolutely astonished by this. For pure quartz crystal is one of the hardest materials in the world. On the Mohs scale of hardness, used by gemologists, it is only slightly softer than diamond. This makes rock crystal an incredibly difficult material to carve, particularly given that it is also somewhat brittle and has a tendency to shatter. The workmanship on the skull was so exquisite the team estimated that even if the carvers had used today’s electrically powered tools with diamond tips, it would have taken at least a year to carve such an incredible object. But the team concluded something even more surprising than this. They felt that it would have been almost impossible to make such an exquisitely carved object using any known type of modern diamond-tipped power tool. This is because the vibration, heat and friction produced by such tools on such a delicate object as the lower jaw would actually have caused the skull to shatter – a fact which apparently led one member of the team to comment, ‘This skull shouldn’t even exist!’
But the original investigating team’s belief that the skull had not been made with modern tools was more than just a hunch. It was borne out by further tests. Even under extreme magnification of the surface of the skull there was no evidence of modern tool markings, no evidence of the usual tool ‘chatter’ or of the tell-tale pattern of repetitive parallel scratch marks. Given that any such markings would have been extremely difficult to remove, these findings seemed to confirm what the team had already begun to suspect – that the crystal skull had actually been made by hand!
This was phenomenal, as the only hand-carving techniques for crystal currently known take an incredible length of time. The scientists could only assume that the skull had been carved by slowly and patiently rubbing the original block of quartz down by hand, probably using a mixture of river sand and water. Even with the use of copper rods or hand-held carving ‘bows’, the team concluded that the crystal skull must have taken several generations of effort to carve! Whilst the precise length of time this had taken was impossible to confirm, the Hewlett-Packard staff magazine Measure put the nearest estimate at ‘300 man-years of effort’!1
As Jack and Charles explained, whoever made the skull would have had to have started with a huge chunk of angular quartz crystal around three times the size of the finished skull, and when they first started carving they would have had no way of knowing whether the inside was pure or full of fractures and holes. They would have had to carefully grade the sand by the size of each of its grains, starting with the largest grains to rough out the overall shape and gradually reducing their size as the work became more detailed, right down to a microscopically fine grain size, like powder, to finish off the final smooth polish. What is more, if they had made a mistake at any point, they would have had to start again from scratch. If even a single grain that was too large had fallen onto the surface on which they were working as they neared completion of the skull, they would have had to start again. This must have been a truly formidable task.
I explained that I had heard the rather outlandish theory, suggested by the ancient legend and also by many of those who had spent considerable time with the skull, that the skull might actually have been made by extra-terrestrials. After all, if it could not even