Important item in 2nd Chronicles - spoilers

[RandomHaruchai]

Looking at the history given for

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the Staff of Law, we know that Berek created it from a branch of the One Tree.

Minor question: How did he know how to find that? Or that it even existed?

Anyway,

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when a second Staff is created,several 'ingredients' are used.

What purpose does each serve?
Did

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Berek

omit or overlook something? Was it something akin to Mhoram's epiphany about the Lords' use of Earthpower for fighting?
If these questions are answered later in the story than

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Findail being found onboard Starfare's Gem in TOT

, please don't spoil the reveal.

[High Lord Tolkien]

Interesting story regarding the creation of the second staff.
Donaldson thought one aspect or ingredient was obvious that many (ok, maybe just me) didn't pick up on.
This was revealed in between the 2nd and 3rd Chronicles.