A researcher accidentally discovered a rare copy of the Magna Carta when searching through a scrapbook in the British town of Sandwich.

The Medieval charter, commissioned by Edward I in 1300, was discovered by a Kent archivist when he was retrieving a document from a Victorian scrapbook, the Magna Carta Project announced Sunday.

The original Magna Carta, created in 1215, was drafted by the Archbishop of Canterbury to curtail the power of England’s King John. There are only 24 editions of the document in known existence around the world. The discovery of the Sandwich Magna Carta brings the total number of surviving originals of the 1300 edition to seven.

Although the copy has suffered extensive moisture damage and is missing about a third of the original text, Professor Nicholas Vincent, of the University of East Anglia, told The Guardian that it could be worth $15.2 million.

“And,” he continued, “it is very likely that there are one or two out there somewhere that no one has spotted yet.”

The Archbishop of Canterbury drafted the very first Magna Carta, which established modern democratic rights, in 1215.

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