Well, my boyfriend is mad at me because I lost a crystal necklace that he had gotten for me 2 weeks ago and it was pretty expensive to me and him (80 USD) for we are just freshman in university. I was having an exercise training for upcoming events in church and I took off the necklace and place it in my bag. But a day later I realize it was no longer in my bag. The first thing that pop into my mind that it must have dropped out of my bag when I was taking my car keys out. But Im 100% no one stole it. What do you think I should do to make him not mad at me for my unintentional action? I've search the perimeters of everywhere I go and I just couldn't find it at all. HELP! :(

Offer to pay him his share back. Give him time to get over it! Pay attention, a guy who cannot forgive an honest mistake, or holds on to anger too long, bears watching.

You really shouldn't need to do anything... why is he still mad? You didn't lose it on purpose.