This monogram is from a 14th century Manuscript Alphabet book which resides in The British Museum in London, England. 

Monogram: E

Accents/Accessories: Smooth background; Smooth loose bail; Central monogram

Size: 31 x 22 millimeters (1.22 x 0.87 inches)

Weight: 6.90 grams (0.24 ounces)

Sterling Silver Chain as shown: 16 inches - $25.00 or 18 inches - $35.00