THE TEN COMMANDMENTS SCROLL that was on display at the Royal Ontario Museum exhibition of the Dead Sea Scrolls was, according to the Jewish Tribune, the Nash Papyrus:

ROM ‘very gratified by response’ to Dead Sea Scrolls exhibit
Written by Atara Beck
Tuesday, 20 October 2009
TORONTO – Since the June 27 opening of the Dead Sea Scrolls exhibit, more than 160,000 visitors have gone to the Royal Ontario Museum (ROM) to view the display, which is “about ideas and values as much as artifacts and ideology,” said William Thorsell, the ROM’s CEO.

A week ago Saturday, the exhibit’s eight scrolls were replaced by eight others, on loan with 200 artifacts from the Israel Antiquities Authority. The exhibit, titled Dead Sea Scrolls: Words that Changed the World – complemented by full interpretations, translations and background information – includes items from the ROM’s own collections as well.

Also on display until Oct. 18 was the oldest known text of the Ten Commandments. The Nash Papyrus, discovered in Egypt, is in Hebrew and dates back to 150-100 BCE. Followed by the famous Hebrew Shema Yisrael prayer, many experts believe it may have been a piece used for prayer rather than a part of Deuteronomy. I

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That's news to me, and it contradicts this earlier report, which says the Scroll was discovered "at a cave near the Dead Sea in 1952" and dates it to the Herodian period. The Nash Papyrus is not a Dead Sea Scroll: it was discovered long before them and in Egypt. There seems to be some confusion on whether the fragment on display is the Nash Papyrus or a Deuteronomy fragment from Qumran, which was on display in the San Diego exhibition two years ago.

Images of the Nash Papyrus are here (Wikimedia Commons). I saw it in Cambridge in 2003. More background to the ROM exhibition here.

UPDATE (1 November): A reader reports that the scroll on display was 4QDeutⁿ.