This small bowl is unmarked I believe it is made by Three Rivers Pottery as it matches other pieces i have exactly except there is no back-stamp on the bottom. I believe this may have been a dip or condiment holder from a chip and dip set.

Measures approximately 5-1/8" in diameter at top 2-1/2" diameter at the bottom and 2-1/4" tall. 

Condition The side has a portion where the glaze is thick like a paint run Please see pictures.

Wh Bin 21