Gmar chasima tova.
You translate sandalvonim sanhedrin 59b as sardonyx. I would appreciate if you emailed me your source for that.
Yitzy Lieberman, London, UK
The Girsa we cited (Sandalchonim, with a Chaf, rather than Sandalfonim) has its source in the Aruch. The Aruch, in turn, is based on the Targum to Iyov 28:18. The translation we cited was taken from Marcus Jastrow's Talmud dictionary, who probably based himself on the similarity of the words and the fact that sardonyx was a familiar gem in Roman times.
Interestingly, according to http://www.firemountaingems.com/resources/encyclobeadia/gem-notes/gmstnprprtssrdn , among the properties attributed to sardonyx are bringing lasting happiness and stability to marriage and partnerships. Perhaps the Gemara is alluding that had Chava not allowed the serpent to seduce her to sin and cause Adam to sin, the serpent would have strengthened the relationship between Adam and Chava rather than weakening it.