This is a beautiful antique Karl Karst 800 silver brooch. It is marked "800" and "Karst". We believe the mainly blue center with small areas of red is man-made; possibly glass or enamel. The brooch is in good antique condition, the non-silver clasp is a replacement and the back of the center appears to have been painted black. The brooch measures approximately 1 7/8" by 1 3/8" and weighs approximately 10.44 grams.