This knife is made of artificial sapphire which is harder than any other gemstone except diamond. Sapphire is the single-crystal form of aluminium oxide that can be found naturally as gemstones. And of course, it cannot be detect by any sort of metal-detector as it’s a fully non-metal knife. You can scratches glass with this without any difficulty and the blade can be sharpened only with a special diamond whetstone.

Neatorama:
“While the technology required to build a usable sapphire knife is pretty neat, it raises significant airport security concerns. Hopefully this doesn’t mean that I’ll be subjected to full bag and body searches in the future!”

[via English Russia]