Up for sale is an extremely rare 18th century (1700's) Stengel? cobalt blue glass cider mug, cup, or glass that is hand blown and hand painted with a monogram that appears to be "Gluck" written in fancy script in the center. This mug is either American or German in origin, and either is or resembles Stengel or Stengl glass. 

Unique and rare, this cup is made of heavy cobalt blue glass with an hourglass shape, a slightly flared lip, and a thick applied handle. There is a rough pontil on the bottom. 

The central design resembles a shield outlined in gold or yellow, blue, and red. This decoration may have been applied after the making of the mug. This is a rare and highly collectible piece of 18th century cobalt glass.

The fifth photo is of the inside of the cup. The sixth photo is of the bottom of the cup showing the pontil.

Age: C1780

Size: 4 1/2" high

Weight: 9.8 ounces (unpacked)

Condition: good, surface wear, "Gluck" barely legible