13 Crystal Skulls.

As an object, skulls are powerfully symbolic. An ancient Indiang legend said that there were 13 crystal skulls of the Goddess Death, and that they had to be kept separate from each other and hidden throughout history.

Archaeologists (and paranormal hunters, ok maybe mostly paranormal hunters) have discovered a few of them:

First, art critic Frank Dordland started investigating the strange skull. After a closer investigation, he discovered that the skull had a complicated system of lenses, prisms, and channels, creating unusual optical effects. The investigator was surprised to discover no signs of processing on the skull's perfectly polished surface. They couldn't be seen even with a microscope. Frank Dordland even addressed Hewlett-Packard, the famous company that specialized in crystal oscillators at that time, for a competent examination of the crystal. ...

Researchers found that the skull had been carved against the natural axis of the crystal. Modern crystal sculptors always take into account the axis, or orientation of the crystal's molecular symmetry, because if they carve "against the grain," the piece is bound to shatter -- even with the use of lasers and other high-tech cutting methods.

To compound the strangeness, HP could find no microscopic scratches on the crystal which would indicate it had been carved with metal instruments. Dorland's best hypothesis for the skull's construction is that it was roughly hewn out with diamonds, and then the detail work was meticulously done with a gentle solution of silicon sand and water. The exhausting job -- assuming it could possibly be done in this way -- would have required man-hours adding up to 300 years to complete.

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