Have you ever wondered what fire is? Like, ok so it’s bright and hot but what is it, really? It’s air. Just bitchin’ hot air. Much like an iron rod stuck in a furnace turns red, the air we breathe glows red when heated through incandescence. Or rather, we start to see this glow after crossing a certain temperature threshold. It’s too weak to be seen with your eyes but even at room temperature objects have this glow which can be shown with night-vision equipment. The heat that gives fire its glow is, in most cases, caused by the union of carbon and oxygen atoms; an exothermic reaction, if you’d prefer the fancy term. You marry carbon to oxygen, that is you oxidize it, and you get a molecule of CO2 (or sometimes its feared monoxide, CO) plus heat.

By now you’re probably sick to death hearing about carbon’s role in climate change. The carbon dioxide content in the atmosphere has increased at an alarming rate. From below 300 parts per million a hundred years ago to an average of 415ppm currently. Despite the most stern warnings from scientists and activists alike, that rate keeps increasing at an annual clip approaching 3ppm, making a mockery of efforts to curtail this dreadful progress. But I bet you didn’t know that there’s another form of carbon that’s also significantly contributing to global warming: carbon itself.

We know that white surfaces reflect light and keep cool while the darker the shade the better it is at turning those sun rays into heat. And, you see, carbon is as black as… eh, carbon is basically synonymous with this color. Soot, lampblack, petroleum, charcoal and ink are all basically carbon in disguise. The combined effluent of millions of chimneys and vehicle exhaust pipes contribute, in addition to the CO2 emissions, a staggering amount of these black particles into the atmosphere. They have three different ways to add to the problem. One by directly converting sunlight into additional heat, secondly by messing with cloud formation and, lastly, by landing on snow fields, reducing their ability to reflect light. The net effect is that it may contribute as much as half of the warming as does the dioxide but is receiving only a tiny fraction of the attention. What good is it, I suppose, to raise the alarm when it’s all bound to fall on deaf ears anyway?

What any of this has to do with this ampule, I agree, ain’t much because it houses that other, much more beloved form of carbon known as diamond. 99.99% pure means 0.01% impure and, amazingly, just that weensy bit is enough to lend color to this famous gemstone. In this way it’s similar to other gems like rubies and emeralds where vanishingly small trace elements have an outsize effect on their color. For carbon, fewer than 1-in-10,000 atoms of nitrogen in the crystalline structure is all that’s needed to lend these crystals an otherworldly bronze hue. Their too-small-to-fit-on-a-ring size on the other hand ensures they can remain affordable.