How can I go about telling him?

My fiancee proposed to me in january...And The ring he proposed to me is not an engagement ring.. It's more a cluster of diamonds. Engagement rings are one diamond ring.. I thought engagement ring suppose to let other guys know Im taken..But it don't! When I be like im engaged they be like wheres the ring I show them and they be like that's no engagement ring....How can I tell him I really don't like the ring like that. I know it came from his heart but....Im not happy with it :(