Vanadium is a metal, and by far its greatest use is in steel
alloys, where tiny amounts of vanadium improve steel’s hardness, toughness, and
wear resistance, especially at extreme temperatures. As I reported in my book
What Things Are Made Of, more than 650 tons of vanadium was alloyed with iron
to make the steel in the Alaska Pipeline, and there’s no good substitute for
vanadium in strong titanium alloys used in jet planes and other aerospace
applications.
Vanadium isn’t exactly one of the well-known elements, but
in terms of abundance in the earth’s crust, most estimates indicate that
there’s more vanadium than copper, lead, or tin. But it’s difficult to isolate,
and it wasn’t produced chemically as a chloride until 1830, when Swedish
chemist Nils Sefström named it for the Norse goddess of beauty, Vanadis,
perhaps better known as Freyja. It wasn’t until 1867 that pure vanadium metal
was isolated by British chemist Henry Roscoe, whose work on vanadium won him
the name of the vanadium mica roscoelite.
As a mineral collector, I’m attracted to vanadinite, lead
vanadate, because it forms beautiful hexagonal crystals, often bright red and
so abundant from one lead-mining area of Morocco that excellent specimens can
be had without mortgaging your house. Some vanadinite crystals are like perfect
little hexagonal barrels, and others can form needle-like spikes around a
central crystal, making the whole thing look like a cactus with caramel-orange
spines.
Some of the vanadium for making steel alloys comes from
primary mined vanadinite, but much more was once produced as a by-product of
phosphorous manufacture, because it’s commonly associated with phosphate rock. And
today, a lot of the world’s vanadium comes from refining crude oil and from fly
ash residues, which are products of coal combustion. I got curious about why
vanadium metal is so closely connected with these organic deposits.
Crude oil actually has lots of trace elements in it,
including metals like gold, tin, and lead, but by far the most abundant are nickel
and vanadium, as much as 200 parts per million nickel and 2000 parts per
million vanadium in some crude oils, especially heavy, tarry oils like those
found in Venezuela. In some oil, the nickel and vanadium can add up to 1% by
weight of the oil, an incredibly huge amount. Refining Venezuelan crude gave
the U.S. a lot of vanadium back in the late 20th century. But why is
it in there?
Oil and coal are both the result of decaying and chemically
changing plant matter. Forget dinosaurs; virtually all oil, natural gas, and
coal comes from plants – usually marine algae for oil and gas and more woody,
land-based vegetation for coal. There’s a class of organic molecules call
