science

I believe that the metals in the crust are primarily

1. because the crust froze, before the heavier stuff could all sink down to the bottom, the core, through convection & settling..
2. from nickel-iron meteorites, like in Sudbury ( a mining-region of Ontario Canada, which is a roughly-200-km wide crater/impact-site rich in metals )
3. because the subducted-crust tends to come back up, through plate-tectonics
4. only waaay-down on the list, because the dino-killing impact apparently burst a batch of volcanoes on the opposite-side of the planet, & THEY carried some of the core's metals out onto the surface ( the iridium-rich layer that coats the planet right when the dinosaurs got extinguished couldn't have come from carbonate-meteorite, & that's what testing has declared the dino-killing meteorite to be, therefore the burst of volcanoes which suddenly appeared on the opposite side of the planet must have been the source for all that iridium )

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