diamond wiki:
>For other uses, see Diamond (disambiguation). Diamond is one of the two best known forms (or allotropes) of carbon, whose hardness and high dispersion of light makes it useful for industrial applications and jewelery (the other equally well known allotrope is graphite). Diamonds are specifically renowned as a mineral with superlative physical qualities - they make excellent abrasives because they can only be scratched by other diamonds, which also means they hold a polish extremely well and retain luster. About 130 million carats (26,000 kg) are mined annually, with a total value of nearly USD $9 billion.
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purple wiki:
[he history of cryptography, 97-shiki-obun In-ji-ki (ä¹ä¸å¼æ¬§æå°åæ©) ("System 97 Printing Machine for European Characters") or Angooki Taipu B (æå·æ©Bå) ("Type B Cipher Machine"), codenamed PURPLE by the United States, was a diplomatic cryptographic machine used by the Japanese Foreign Office during, and just before, World War II. The machine was an electromechanical stepping-switch device.
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