Due east of C. Mayer is the flooded crater Kane.

C. Mayer is a relatively young formation, with a sharp-edged and well-defined outer rim.

The rim is not quite circular, and appears somewhat polygonal-shaped with outward bulges along the edge, most notably to the west.

The central peak lies just to the north of the midpoint, and extends in a northerly direction.

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to C. Mayer (See the C Mayer D crater that is very similar in shape to the map of Brazil).