A Campo del Cielo iron nickel meteorite from Argentina. These meteorites were discovered in 1576 but fell much earlier, around 4,000 - 5,000 years ago. They are believed to be 4.5 billion years old and may have came from the asteroid belt between Mars and Jupiter.
This particular piece is what's known as a 'shattered crystal'. These crystals are formed by freezing a larger meteorite in liquid nitrogen and then shattering it.