Quote:
The formation of Ni-poor kamacite proceeds by diffusion of Ni in the solid alloy at temperatures between 700 and 450 °C, and can only take place during very slow cooling, about 100 to 10,000 °C/Myr, with total cooling times of 10 Myr or less. This explains why this structure cannot be reproduced in the laboratory..... nickel-iron crystals grow to lengths of some centimeters only when the solid metal cools down at an exceptionally slow rate (over several million years)
- Myr = million years