They tell us in meteor school that - besides the usual litter of S-, C-, and metallic asteroids/meteorites - we also get stuff knocked here from other planets. This stuff doesn't contain the chondrules of the usual rubblepiles; thus, are "achondrite", from something that differentiated before knockoff. Suspects include the Moon obviously; Mars has furnished a few more, [UPDATE 7/25 and even Earth has coughed up some stuff as has come back]. But another exporter of meteors our-way is/was Vesta.
And not Venus. Which is another question I'd like answered someday; when Venus gets hit it gets hit hard. But maybe Venus' atmo and gravity together have prevented rocks from launching their way out into Earth-intersection. Anyway we're here for Vesta.
Vesta is perhaps the true missing planet; Ceres being a Centaur having drifted here after-the-fact. Vesta is differentiated like a planet. But it since got whacked Venus-hard by other rocks, so it's not a spher[oid] anymore (Ceres is still mostly spherical). The mass liberated from Vesta's crust and mantle had to go somewhere. Much of it still floats in a Vestal group of asteroids, which includes some interlopers of their own, but is mostly of a similar type, dubbed the V-type. A bit of S, a bit metallic; dependent on how far down the initial whack had whicken.
So: why do we get any V down here? Answer: some of those V's had been blown into a 3:1 or 4:1 resonance with... Jupiter. That's a Kirkwood. These will get pulled more-and-more eccentric; and they don't get pulled very far up/down for inclination. By harsh luck Earth is 11.8:1 to Jupiter so a 3:1 to Jupiter is near 4:1 to us.
It gets more fun when you see that some of these elongated V's are... large. 10 km range. They've caused some craters here already.
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