Town mark silver of Ath, a cross in a contoured shield. Year 97 for 1797.
Silversmiths only established their own guild in 1662. Its mark is taken from the city's coat of arms. For more information see;
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Unfortunately many silversmiths of Ath, 18th century are today unknown. I will let you know if anything comes up.
Peter.
Source; R. Stuyck, Belgische Zilvermerken/Poincons d'argenterie belges