A: Two animal-headed human-like figures on double ground line with x figures in the space. The figure on the left with the head of a lion (Horus), the figure on the right with the head of a donkey (Seth). Both of them wearing kilt and shoes. Around Horus' head nimbus with seven double rays. Navels and nipples given with lines. Under the outside arms of both figures rope-like notches. The other arms of the figures reach out towards a rhomboid object with a medial axis at the top crowned by a ring. This is a misunderstood representation of the ancient Egyptian smA-tAwy symbol (union of the two lands), and the gem, which is thus an example for the survival of Egyptian hieroglyphs on magical gems, contains the idea of "uniting something that belongs together".
B: αεεη|ηηιιιιοο|οοουυυυ|υυωωω|ωωωω → The Greek vowel series. The inscription is a graphically unmarked pterygoma.
Bibliography
Bonner 1951 on CBd-137
Michel, BM on CBd-137
The British Museum Collection database on CBd-137