Take a look now. I cleaned up the picture and magnified it a little. Should be better. I also think I see a "A" in it. Now I will leave it to the real experts.
I believe that it is a Roman Catholic medal. The legend/inscription "VT VNVM SINT" (Ut Unum Sint) Is Latin for "May They Be One," a reference to Christ's words...
"My prayer is not for them alone. I pray also for those who will believe in me through their message, that all of them may be one, Father, just as you are in me and I am in you. May they also be in us so that the world may believe that you have sent me. I have given them the glory that you gave me, that they may be one as we are one: I in them and you in me. May they be brought to complete unity to let the world know that you sent me and have loved them even as you have loved me" (John 17:20-23).