A rod of raw titanium. (Photo: Alchemist-hp/CC BY-SA 3.0)

Titanium, as you’ve probably heard, is the hardest naturally-occurring metallic element, which is why doctors use it for things like knee replacements, because it is hard, reliable, and not toxic. 

It wasn’t discovered until 1791, but even if we had known about it, we still would have invented steel, which can be made with much cheaper materials, and is many times harder than titanium.

Still, titanium has its uses, and some scientists recently figured out a way for it to compete with steel, at least in terms of hardness: by mixing it with gold. Three parts titanium, one part gold, to be precise.

The scientists, who recently published their research in Science Advances, said they weren’t sure if they were the first to actually discover the new alloy, but they were sure they were the first to document it. 

The discovery was a bit of an accident. The team had made several alloys as part of a separate project, after which they were to grind them into a powder to study with an X-ray. 

But “when we tried to grind up titanium-gold, we couldn’t,” said Emilia Morosan, a professor at Rice University and study co-author. “I even bought a diamond (coated) mortar and pestle, and we still couldn’t grind it up.”

The alloy, Morosan said, is “three to four times harder than most steels.” Watch your back, steel, titanium is coming for you.