In Eclispe the book, Alice is saying something about diamonds on Bella from Edward. What in the world does that mean?

They are in the nhà để xe and just about to go camping. Bella and Alice just got done taling about Alice doing the wedding. She says "Hmm, i thought i saw him put it on you. Yep." (Edward) Bella has issues with jewerly. "Does it make a difference he aready has a dimond on you."-Alice. I dont think it is the tim, trái tim that he gave her either.. Thanks.! <33