This is a Japanese Nippon hard paste porcelain mug. The date is circa 1910.
The mug is 5 5/8” high and 4” wide at the bottom.
The front of the mug shows the head of a hand painted elk, or a deer that looks like an elk. The ground is shaded in brown. Around the bottom and top, and matching the handle, there is a band of ground in green with raised enamel and bordered in brown. The back of the mug shows a cluster of acorns nestled in green oak leaves.
There is minimal wear. One side shows the faint outline of a mold line. There are a few specks of missing enamel. There are no chips, nicks or cracks.
This is an original Nippon mug.
The green mark is M in the wreath with Hand Painted above and Nippon below.