[eizositc] Forging Widmanstatten patterns

The crystallization pattern inside metal meteorites forms over millions of years of very gradual cooling, so is supposedly impossible to artificially create. Thomson-Widmanstätten structure.

However, I am skeptical:  Although the cooling took millions of years, for much of that it was too hot for crystallization to occur, and also for much of that, it was was too cold.  Most of the crystallization probably occurred within a relatively short time frame at a critical temperature.  Recreate such conditions in a lab with an incubator.  Perhaps years or decades is enough. What is the critical temperature?

If they truly are impossible to counterfeit, one can imagine such meteorite pieces used as currency, perhaps black market.

Are there structures even more difficult to create, perhaps not yet ever seen by the human eye? (That are stable at standard temperature and pressure, so not neutronium.)