First written record of Semitic alphabet, from 15th century BCE, found in Egypt

"Newly deciphered Egyptian symbols on a 3,400-year-old limestone ostracon from Luxor’s Tomb of Senneferi appears to be the first written evidence of the ABC letter order of the early Semitic alphabet, according to a University of British Columbia Egyptologist.

In his article, “A Double Abecedary? Halaham and ‘Abgad on the TT99 Ostracon,” Prof. Thomas Schneider concludes that a small (approximately 10 x 10 centimeters, or about 4 x 4 inches) double-sided limestone flake was used by Egyptian scribes as a mnemonic device to remember the letter orders of not one, but two forms of early Semitic alphabets."