Use the difference in price on a down payment on a home/apartment or open a college savings account for your kids. Tell the truth, you want to build a life together and are thinking about the long term financial and personal consequences of this decision. I bought a ruby for my wife for this exact reason. I also wanted to show our community that we rejected diamonds as a tradition. I think the more we discuss this issue the more likely social conventions will change so future couples won't have to have a discussion.