My Fiance and I just picked up our wedding rings made my a close friend of his dad''s girlfriend. My ring is an eternity band that is platinum however there is no stamp on the ring to indicate this. My fiance''s ring is a handmade platinum band with milligrain edges. We came home and examined his ring and realized it said "750" inside. Isn''t 750 18k gold and not platinum? Also..has anyone ever heard of a plat eternity band with no stamp to indicate this on the inside? Please help...wedding in 3 days and we are very upset!