u/Ghosty_crafts_

I was recently researching zircons and how they're used to date things but I can't get my head around why the Jack Hills zircons being 4.4 billion years old is hailed as the primary way we dated the Earth when the Earth is 4.54byo.

From my understanding, (I have a very sparse geologic backing mind you) the 4.45 was established by dating meteors (or whatever the correct name for it is.) Are the JHZs significant because we know they originated on Earth so they confirmed that it was at least 4.4byo, therefore this made the 4.45 reasonable and it is assumed that the meteor and Earth formed at the same time?