Although the internet has spawned a multi-billion dollar industry in creating and cracking codes, crypologists have yet to solve some of the oldest riddles. Below are ten of the most notable:
1. The Phaistos Disk is considered the most important example of hieroglyphic inscription from Crete. Discovered in 1903, both sides of the clay disc are covered with hieroglyphs arranged in a spiral zone, impressed on the clay when it was damp. Forty five different types of signs have been distinguished, of which a few can be identified with the hieroglyphs in use in the Proto- palatial period.
2. Linear A is one of two linear scripts used in ancient Crete discovered and named by Arthur Evans. Linear B was deciphered in 1952 by Michael Ventris and was used to write Mycenaean Greek. Linear A is partially understood but parts of it produce works unrelated to any known language.
3. Kryptos is a sculpture by the American artist James Sanborn, located on the grounds of the Central Intelligence Agency in Langley, Virginia. Since its dedication in 1990, there has been much speculation about the meaning of the encrypted messages it bears.
4. Chinese Gold Bar Cipher. In 1933, seven gold bars allegedly issued to a General Wang in Shanghai, China. These gold bars, which contain pictures, Chinese writing, some form of script writing, and cryptograms in Latin letters, appear to represent metal certificates related to a bank deposit with a U.S. Bank and the Chinese writing has been translated, and discusses a transaction in excess of $300,000,000.
5. Beale Ciphers are said to be three encrypted messages which pinpoint where a man named Beale buried two wagons-full of treasure at a secret location in Bedford County in the 1820s. It is claimed one of the messages has been solved, which detailed the tons of gold, silver and jewels that were buried, along with a general location. The still unsolved messages supposedly give exact directions, and a list of who the treasure belongs to.