When pressed for information, an astrophysicist friend at UCLA wrote:

“Well, a pallasite is a kind of differentiated meteorite, which means it was a part of a large asteroid that was big enough and hot enough to melt. When that happens, all of the heavier iron sinks to the center, and the lighter rocks rise to the top; what you end up with is something that looks like a miniature Earth, with a core, a mantle, and a crust. Then something big hits that asteroid and breaks it up into a bunch of little pieces. Think Alderaan in Star Wars.

 

So now you have these little pieces of a former miniature planet floating in space. Iron meteorites were the core of the asteroid, and there are things called Achondrites that were the mantle of the asteroid. Right at the boundary between the core and the mantle, there were crystals of olivine (i.e. Peridot) floating around in molten iron. Those are pallasites - bits of the asteroid that were on the border of the core and mantle. If you look in my photo album here, you’ll see me holding a spectacular example of one.

 

I don’t know much about the specifics of your pallasite, other than it has a high iridium content and seems to be pretty rust resistant. In case you want a fun fact about iridium, scientists find iridium in high concentrations all over the world in a layer of clay 65 million years old. Iridium is rare on the surface of the Earth, so it’s very likely that the Iridium came from an asteroid.  You know what happened 65 million years ago? The mass extinction of the dinosaur. It was the discovery of the iridium that led scientists to conclude that a giant asteroid was what killed off the dinosaurs!”