Art Deco Porcelain Jaeger? Cup/Cup Bowl Eggshell China

Lovely Art Deco design Cup and Saucer in very thin eggshell china. It has black trim, rust hand painted flowers and is a cup bowl, not a saucer. The mark on the bottom is simply a J C in black stamp. My friend thinks it may have been made by Jaeger which is a German company. Circa about 1912. Both cup and saucer are mint condition. The saucer/bowl is 5 1/4 inches in diameter and the cup is 1 3/4 inches tall and 3 1/2 inches in diameter. Thanks for looking!