It's a pallasite stony-iron meteorite, containing olivine (the yellow-green crystals) nested in an iron-nickel alloy.
These are believed to either have formed at the boundary of an asteroid's core and mantle, or to have formed when two asteroids or planetesimals impacted into each other, melting and fragmenting components of each.
The iron-metal alloy can form a Widmanstätten pattern (criss-cross) due to intergrowths of two types of this alloy: kamacite (low nickel) and taenite (high nickel) that occur due to the slow cooling of the metal in an oxygen-poor or -absent environment.
I'm still learning so some of these might be incorrect, please correct me if you spot any errors!
These are believed to either have formed at the boundary of an asteroid's core and mantle, or to have formed when two asteroids or planetesimals impacted into each other, melting and fragmenting components of each.
The iron-metal alloy can form a Widmanstätten pattern (criss-cross) due to intergrowths of two types of this alloy: kamacite (low nickel) and taenite (high nickel) that occur due to the slow cooling of the metal in an oxygen-poor or -absent environment.
I'm still learning so some of these might be incorrect, please correct me if you spot any errors!