Recently, a good friend of mine asked me if he could propose with the same ring he’d given to his first fiancé. Maybe he thought that as I knew about diamonds I would also know about the norms surrounding jewelry.

I didn’t. I’ve never asked anybody to marry me, let alone done it twice. (Honestly, I’m not sure whether I’m more scared of them saying ‘yes’ or ‘no’.) And so the question had never occurred to me.

Nonetheless, I was happy he asked. I love questions like these. They allow you to explore facets of our existence you otherwise wouldn’t have known existed.

It turns out that there are two facets to this question which can be summed up as:

1. The financial cost
2. The relational cost

Let’s handle these in turn. (Warning, history ahead!)

The financial cost

Engagement rings are a horrible investment. The act of buying one means that you’ve just lost somewhere between 1/2 and 2/3rds of the ring’s value. Ouch!

The reason? The retail markup on diamonds is high (between 100% to 200%), which in turn is because of some clever marketing. You see, diamonds aren’t actually as rare as they’re made out to be. Yes, back in the day they were. Only a few pounds were found most years.

But then, in the late 19th-century huge diamond mines were discovered that literally had tons and tons of the things. The price has been kept high by the people that control those mines, which was for most of history the De Beers Consolidated Mines, Ltd.. They’ve simply restricted how much they dug up.

The thing is, just because production has been restricted doesn’t mean there are fewer diamonds. They’re just coming out of the ground more slowly. The producers know this. The jewelry manufacturers know this. The shops know this.

In fact, many shops get their rings on consignment. That means they don’t pay the manufacturers unless they find a buyer. So why would they sink their money in buying back your ring?

Sure, there are companies out there that you can sell rings to. To make it worth their while, though, they have to buy back rings at under wholesale prices. Yes, you read that correctly, ‘wholesale’. That’s the price before that 100 to 200% markup.

So yeah, the financial cost is high.

The relational cost

So does that mean I’m saying ‘go for it, give her the ring you’ve already got’? Not quite. You see, people are not impressed by the idea of you using the same ring twice. Responses on forums to the question ‘can a man propose to two women with the same ring’ have quite a range.

On one extreme I found ‘it’s a bit tacky’ (from a guy). At the other end was ‘dump him, dump him immediately [scream of unintelligible rage at the stupidity of men]’ (yeah, that one was from a girl).

Now, you might think the latter a bit extreme. At the same time, I understand where she’s coming from. After all, she’s been the target of some persuasive marketing that started long before she was born. (Okay, maybe it didn’t. She might be one of those 100-year-old tech-savvy grandmothers trolling the forums. Point taken).

Whose marketing? Yup, you guessed it, De Beers Consolidated Mines, Ltd.

These guys didn’t just influence production, they’ve influenced consumption as well. All the way back in 1938 they started a concerted campaign to connect diamonds with marriage, love and a woman’s self-worth. They put diamonds in movies, in glamour shots and on the hands of famous people. They created the idea that a man’s love could be measured by the size and price of the stone.

When they started only a small percentage of US couples received diamond rings. Now it’s a global custom, seen in all cultures and income levels. So yeah, you can say this worked.

They didn’t stop there, though. They realized that to keep the price of diamonds steady they needed to make it anathema for people to sell them. And this they did. People don’t sell their diamonds because to do so is to betray their love!

And so, most diamonds are locked in. People pass them on as heirlooms, thinking they’re doing their families a huge favor by doing so. Of course, you now know that’s not the case (Did I mention they’re a terrible investment as well?).

The upshot? You’re going up against 80 years of marketing that says that if he doesn’t buy her a new ring, he thinks she isn’t worth it. And as you’re probably struggling to convince her that it’s okay to leave the toilet seat up, that’s a battle you’re likely to lose.

Have you considered resetting it?

Of course, there is a third option and that’s the one I advised my friend. I told him, why don’t you have the same stone reset into a new band? Then you’re avoiding the costs of selling one diamond to buy another, while still giving her a new ring.

And that allows you to avoid all the stigma of giving the ring meant for one person to another. A lot of jewelers will gladly do this kind of thing for you. As they can sell or reuse the metals (there isn’t quite as much of a markup on that) you’ll only have to pay for craftsmanship.

Hey presto! A solution! My friend was happy with the idea. I was happy that I’d learned something about how diamonds and marriage were connected in the first place.

But what about the family heirlooms?

Of course, there is a tail to this tale. What about those heirlooms you’ve got lying around? What if you or your parents actually sunk serious money sunk into them? In that case, if you don’t have any emotional connection with them, think about biting the bullet. After all, they’re not actually making you any money.

My advice? Sell them and re-invest that money into a stock portfolio, land or put it into your retirement plan. In that way, you’ll earn some money, which means your money is actually working for you. That’s better than them just sparkling prettily, no?

If that’s a road you’d like to take, then check out our list of diamond sellers or check out our customer reviews. That way, even if you won’t get what your parent’s expected, at least you’ll get more than you otherwise might. And there is something to be said for that.