You should receive the stone in the mail after completing the achievement. It is possible that it is taking longer than normal for the system to send it out. I'd agree with the others, submit a ticket either in-game or through the Support site.
Compromise is a basic negotiation process in which both parties give up something that they want in order to get something else they want more. Compromises usually occur in win-lose situations -- when there is a fixed pie to be divided up, and whatever one side gets, the other side loses.
a settlement of differences by mutual concessions; an agreement reached by adjustment of conflicting or opposing claims, principles, etc., by reciprocal modification of demands. 2. the result of such a settlement. 3. The split-level is a compromise between a ranch house and a multistoried house. 4. an endangering, especially of reputation; exposure to danger, suspicion, etc.: a compromise of one's integrity. verb (used with object), compromised, compromising. 5. to settle by a compromise.