...but, again, I'm surprised to find myself out of time.

Ferrous metals are generally any metal containing Iron, found about everywhere, and about as commnon as dirt. It’s a very basic metal, such as pure iron, or processed steel.

The noble metals are those which resist corrosion, such as gold, platinum, or silver.

Precious metals are those which are rare, and therefore quite expensive. Some of these include gold, silver, platinum and palladium.

Let's see... Cobalt output for the Democratic Republic of Congo was huge in 2011. I don't have the numbers. Other high producers include Russia, Cuba, Canada, Brazil and parts of Africa. The lower producers were Australia, New Caledonia, Indonesia, China, Namibia, South Africa, Botswana and Zimbabwe.

Titanium can be found just about everywhere, is processed all over the place, but the majority appears to come from China.

Cobalt and titanium are requirements for rockets and high-performance jets.

I’m just throwing out some ideas.

I recall there was an argument made, way back in the 70’s, that the next war would be a desert war, but one directed at embargoes on international mineral deposit operations, basically for fighter engine parts and such.