Welcome to the world of resource and reserve calculations, where the numbers are made up and the points don't matter.
It's very easy to come up with a back of the envelope calculation to say we have this much Lithium, or this much Copper and come up with an absolute whopper of a number, the question is how much of it is recoverable and can it form part of a resource. There's a reason we (mining industry) don't let people produce these kind of numbers offhand, it's wildly speculatory and holds no basis in mining reality (yet!) - however very cool stuff and might provide a new exploration target in the future.
It's very easy to come up with a back of the envelope calculation to say we have this much Lithium, or this much Copper and come up with an absolute whopper of a number, the question is how much of it is recoverable and can it form part of a resource. There's a reason we (mining industry) don't let people produce these kind of numbers offhand, it's wildly speculatory and holds no basis in mining reality (yet!) - however very cool stuff and might provide a new exploration target in the future.