Believe it or not, diamonds did not always go hand-in-hand with love and marriage. In fact, it's only in the last century that they became an engagement ring staple, and the reason why is pretty unromantic. But that doesn't mean they're totally meaningless. If you factor in a little spiritual insight, the diamond as a symbol for commitment makes perfect sense. Prior to the 20th century, diamonds were certainly common in engagement rings, but we have jewellery retailer De Beers to thank for the diamond's eventual dominance. With its 1947 campaign, "A Diamond Is Forever," De Beers made diamonds synonymous with the contract of marriage — unbreakable and precious. The stones were a pricey status symbol before De Beers' acclaimed ad, but the retailer made them an indispensable part of the marriage ritual. Spiritually speaking, however, if you've ever dipped your toe into crystal healing, you may have noticed that diamonds aren't usually mentioned. There are plenty of crystals and minerals that are believed to foster feelings of love and commitment. It's just that they've never been promoted by a hugely prominent jeweller. But, if you're worried that your diamond engagement ring is merely the product of a wildly successful ad campaign, don't lose heart. Though diamonds are not usually considered healing crystals, they can be — and it turns out, they posses quite a few properties that anyone would want their relationship to emulate. For one thing, De Beers was right to draw parallels between diamonds and eternity. They're believed to be one of the most consistently powerful gems, to the point that they don't need to be charged — ever. And then there's the fact that diamonds are incredibly strong, which applies to their spiritual properties, too. Diamonds are said to improve users' stamina, clear their thoughts, and essentially make them feel more grounded, focused, and, yes, committed. That's why it's still totally fitting to give your S.O. a diamond ring if you want to. Compelling ads aside, the diamond represents purpose, dedication, and devotion — and we'll happily wear a ring that says all that.