How can you tell that? The story didn't say, either way.
http://www.israelnationalnews.com/News/News.aspx/157609
“Included among the items found were 108 gold coins, including 93 that weighed four grams each, and 15 that weighed 1 gram each. The gold was not new and clearly was part of someone’s family treasure or business investment. The coins were minted in Egypt approximately 250 years prior to their burial under the floor tiles of the 13th century CE fortress that has been under excavation for more than 30 years.”
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I read elsewhere that they were. There was a name which this type of coin were known by, but I did not find it when I searched to try to answer your question.