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.
In compromise situations, neither side gets all of what they really want, but they each make concessions in order to reach an agreement that is acceptable to both. There are two principal ways to negotiate a compromise. The first is for the parties to go back and forth with offers and concessions until they meet somewhere in the middle. This usually takes place around a single issue, such as the price of an item. For example, Juan and Antonia want to buy a house that is on the market for $200,000.