Antique snake ring with 2 emeralds, diamond roses in total approx. 0.5 ct

antique snake ring with 2 emeralds, rose-cut diamonds totalling ca. 0.5 ct, and ruby eyes, different gold alloys and silver, 9.9 g, ring size 50, ring shank with engravings and remains of black and white enamel, cross over shape with 2 heads, 2nd half of 19th century, signs of age, repair and wear, connection point at heads loose.