iron-rich meterorites. Consisting of kamacite and taenite and formed under extremely slow cooling conditions—about 100 to 10,000 °C/Myr, with total cooling times of 10 Myr or less—it will precipitate kamacite and grow kamacite plates along certain crystallographic planes in the taenite crystal lattice. See also List of minerals List of rocks List of rocks on Mars Petrifaction Rock cycle References External links The rock forming process, on sci-culture.com Petrology