The coins may have been stolen while the museum was understaffed during a strike over wages last month.
“We have been made aware of the incident, which is extremely unfortunate,” a PCS spokesman told the Edinburgh Evening News. “There is some speculation that this may have happened during the recent strike. If this was the case then management have put these exhibits at risk by opening the museum with a skeleton staff.”
He added, “We would hope that management would get around the table to resolve this issue,” he said, in reference to the ongoing pay dispute.
However, a spokesperson for the NMS said there was adequate security in place to protect the museum. “We continue to provide appropriate levels of trained staff in our galleries.”