Hi everyone, I found this to be a good read.

http://en.wikipedia.org/wiki/Laterit...

Here's a snippet:

Pig iron oxide ores

A recent development in the extraction of nickel laterite ores is a particular grade of tropical deposits, typified by examples at Acoje in the Philippines, developed on ophiolite sequence ultramafics. This ore is so rich in limonite (generally grading 47% to 59% iron, 0.8 to 1.5% nickel and trace cobalt) that it is essentially similar to low-grade iron ore. As such, certain steel smelters in China have developed a process for blending nickel limonite ore with conventional iron ore to produce stainless steel feed products. This pig iron process short-circuits the typical costly hydrometallurgical route for producing nickel, which is then used in stainless steel anyway.