science

Precisely: the core is primarily iron, in mass, with nickel probably being the 2nd by-mass component. I've read that hydrogen is about 10% of the core's mass ( metallic, obviously ), & that is why the seismic-refraction-index is as low as it is. Platinum, iridium, osmium, uranium, etc, all the heavy stuff, is in there, too.

( that is why the iridium-rich layer covering the entire planet right when the dinosaurs got extincted is significant:

it had to come either from a nickel-iron type impactor, XOR it had to come from volcanoes which somehow got core-metals in them: there's no other source for that much iridium, locally to this planet.

The fact that the impactor has been tested to be carbonate rock, & NOT a nickel-iron body, to me, proves that the impact produced that burst of volcanoes on the opposite side of the planet

( those volcanoes exist: some have claimed that the impact didn't cause dino-extinction .. that it was ONLY those volcanoes ),

..and to me proves that the total input of both impact and burst-volcanoes' energy-expressions is what killed-off the dinosaurs.

Lava isn't heavy-metals-rich normally: we're talking thousands-of-km distance between the bottom-of-the-crust & the outer-liquid-core ( the inner-solid-core is inside the outer-liquid-core ), magma is a HUGELY thick layer.

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