Burden China Mug Cup Black Vintage Restaurant Diner Ware Delicate Handle Set 3

Vintage pre-owned set of three mugs/cups in overall good condition with some minor wear from age. Items are very clean inside. There is what looks to be an uneven take of coloring at tops of cups. I believe this is a normal occurrence at time of manufacturing. The cups have a few small scratches on outside. Close-ups provided to show examples. One cup has what looks to be either an area where color/glaze didn't take or small chips at bottom/base. Please see all pictures for detail and measurements. Approximate Measurements: 3 3/4" high/tall. Items are less heavy than standard restaurant ware.