Choosing a diamond engagement ring is one of the most challenging endeavors for a couple. The option of picking through a parcel of loose diamonds for your engagement ring is very exciting for couples. Diamonds can be a man's best friend.too. Don't overlook the option of asking your diamond professional to bring in loose diamonds to view for your customized diamond engagement ring. You will notice that diamond engagement rings are usually customized per customer, according to fashion sense, value, and quality.