If a man, whose madly in love with you, bends down and asks you to marry him--and he places an opal engagement ring on your finger--then quite obviously, the answer is yes. While your girlfriends are busy gushing over their cubic zirconia, you can have one of the most revered gemstones of the ancients. Stay away from milky white opals. You're looking for "fire." It shouldn't just flicker, it should flash. Embedded, there ought to be a violent storm of color. True, the opal has had a storied history, mostly superstitions and black magic. Regardless, when paired with diamonds, an opal engagement ring would be divine.