'reclaimed' silver and abalone earrings

Pic one is kinda what these looked like when they were found stuck in the accumulated back-corner detrius (uggh!) in what had formerly been a bathroom vanity drawer. (after the big crusty chunks were knocked off with a toothbrush) Something started to look potentially shiny, so they eventually went for a spa treatment with some household cleaner in my jewelry cleaner machine, then a little more toothbrush, and now I've got what's seen in the rest of the pics! :-)

Looks like abalone shell (I think?) set into silver in a leaf shape with veins and a little stem, they're marked "HENCHO EN MEXICO 925AO" on the backs beside the screw posts. That's all I know about them, I guess I should try some actual silver polish gently and see if they get even prettier?? :-) :-) :-)