Researchers using multispectral imaging have discovered a previously undetected inscription on an ostracon from the Arad fortress. The ostracon (a clay shard with ink text), known as Arad 16, was unearthed at the ancient Judean military fortress of Arad in 1965 and has been dated to 600 BC. While the recto (front side) has been studied extensively for years, the verso (back side), was thought to be blank. The recto inscription is addressed to Elyashiv, the quartermaster of the fortress, and begins with a blessing by Yahweh. Using new, advanced imaging several new lines of text on the recto were discovered, and new readings were provided for other lines with the new clarity of the inscription. The previously unknown inscription on the verso seems to be a continuation of the text on the front, revealing more than 50 characters and 17 new words. Most ancient, biblical Hebrew inscriptions that have survived are ostraca; they are often poorly preserved and fade quickly over time once unearthed. This new technique of multispectral imaging will greatly assist archaeologists and scholars in translating and documenting inscriptions on ostraca which may even be invisible to the naked eye.