[ClearCase_guy]

I think the standard estimate for the age of the Earth is 4.5B years.

So Earth was formed first, and then 3B years later, the core formed?

What?

[EEGator]

I think the concept is that there was a core, and that over time it separated into an inner core and an outer core.

[samtheman]

I think the standard estimate for the age of the Earth is 4.5B years.
So Earth was formed first, and then 3B years later, the core formed?

What?

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Before the core formed the center was all molten. The hard ball of solid iron at the center is what is new.

[JimSEA]

No, a solid core formed from a molten core.