This monogram was designed by Henri Renoir in his book Monograms and Ciphers, (1870). 

Monogram: SS

Accents/Accessories: Large twisted bail; Scalloped edges; Detailed background; Raised smooth monogram; Rounded shape

Size: 75 x 53 millimeters (2.95 x 2.09 inches)

Weight: 48.20 grams (1.70 ounces)