There's a slogan about a gemstone that I've been hearing my entire life.

You've probably heard it too.

A diamond is forever, De Beers.

A diamond is forever.

The tagline of the original global diamond company, De Beers.

It was the early version of Put a Ring on it.

My colleague Jenny Strasberg has been reporting on the diamond business, so I gave her a call.

Where did the idea of a diamond engagement ring come from?

What's the origin story here?

In 1947, the slogan that everybody knows,

a diamond is forever, was born.

And it's become one of the most iconic advertising,

marketing slogans of all time.

What it really did is it put into the popular culture, this idea that if you love someone,

here's how you show it.

And the idea that this gemstone would be a symbol of love, commitment, elegance, timelessness,

you know, that was really a manufactured idea to sell diamonds.

And it worked extremely well.

It was brilliant, some might say.

It was.

Throughout most of the last century, De Beers was the main supplier of diamonds to the entire world.

At its peak, how much control did De Beers have over the diamond market?

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