France 1849 - Very rare black 20-centime stamp, canceled with a red grid, on a letter. - Yvert et Tellier n°3

20 centimes black on yellow, very slight archival fold visible only under a loupe, otherwise very beautiful, cancelled by the red grid of a magnificent color, on a letter with no correspondence addressed to Sarrebourg.
On the front the departure date stamp type 15 "La-Petite-Pierre" (4th class distribution office) dated January 20, 1849.
On the back the arrival stamp at Sarrebourg dated January 21, 1849.

Only letter known from this office in January 1849.
Magnificent composition. Signed Calves, Scheller and Baudot, with Certificate