Safely Removing Adhesive Residue from Rose Quartz - Expert Advice

Question
I ordered a rose quartz pendant online & cannot get the seller to answer my question. Adhesive from where the bail was attached has turned black.  How can I remove it and not harm the stone?  Thanks.  

Answer
hello..
we often glue stones to cardboard  ....using a water-based glue..but there have been times where we used either alcohol
or second choice thinner for other adhesives....I do not remember ever cleaning rose quartz so you may want to get a second opinion?