Here's a twist. Up to now, families were named after the partner element. This one is named after how it formed instead.

The definition: a laterite is soil and rock left behind after millions of years of intense weathering — that's rain, heat, and time slowly rotting the rock — in hot, wet, tropical climates. The rain washes away the parts that dissolve and leaves certain metals concentrated near the surface, mostly as oxides.

What they give us

• Nickel laterites — a huge share of the world's nickel, with cobalt alongside it.
• Bauxite — the ore of aluminium. Here's a useful fact to lock in: bauxite is itself a laterite, just one where aluminium got concentrated instead of nickel.

The trade-off that defines this family

Because laterites sit right at the surface, they're cheap and easy to dig — no deep underground tunnels. But the metal is locked up in oxide form, so freeing it is expensive. The go-to method is HPAL — High-Pressure Acid Leach — where sulfuric acid, under high heat and pressure, dissolves the nickel and cobalt out.