Your spoon was made by Victoire-Joséphine Godot, wife of Jean-Joseph Rivet. Godot worked in Paris as a flatware maker (orfèvre-cuilleriste) at 380 rue St-Denis. She registered this mark G.Fe.R., standing for Godot, wife of Rivet, symbol a salt shovel (pelle à sel) on 5 July 1832, erased 6 July 1836. This is the first time I’ve seen a woman who marked as the wife - not the widow - of a living silversmith.
See Arminjon, v. I, no. 01317, p. 155.
Her husband, Jean-Joseph Rivet was the successor of Louis-François Blacet. Rivet registered his mark in 1815-16, erased 5 July, 1832, the date his wife registered her mark. It is not clear whether he retired or was somehow incapacitated when his wife took over the business. His symbol was also a salt shovel, as was that of Blacet, but oriented in the opposite direction to Godot’s symbol.
See Arminjon, v. I, no. 01885, p. 203 and no. 02339, p. 241.
Depending on the length, your spoon in the Filet (Thread) pattern could be a place spoon, rather than a serving spoon.
Hope this helps.