A pair of 18th-century silver flagons has been stolen from Clifton Park Museum in Rotherham two months after £70,000 of lead was removed from the listed building’s roof.

On the night of 9 April, the thieves smashed a window to gain access to the museum.

The silver flagons, which date from the reign of George III, are described as being of plain circular tapering form with a domed hinged cover.

Made by Tudor and Leader in Sheffield, they are 36.5cm high and inscribed: “The Gift of Mrs Mary Bellamy, Late of Rotherham, 1781.”

In March, thieves stole £70,000 worth of lead from the museum’s roof. The theft was discovered when staff noticed rain water leaking into the building.

South Yorkshire Police has appealed for witnesses to either incident.

The rising value of silver and other non-ferrous metals has made museums, historic houses and heritage sites a target of thieves, according to security experts.

Museum Practice: thefts