I am not talking about the physical product but figures on paper, or a screen. It does not vary even if you are talklng about crude of different gravity. Like gold that stays in the vault, it still changes hands.
I don't follow. Unlike investments in gold, crude is bought and consumed, not held. Only the Strategic Petroleum Reserve buys oil to hold, but it doesn't change hands, unless it comes out of the ground and is delivered.
Trading on the market is not trading oil, it is trading the future delivery of oil. But I don't see how that relates to Alaska oil to Japan.
The oil that is produced in Texas and in Saudi Arabia ,all part of the pool of oil available for sale and use. in this respect, it is like the grain produced in the Ukraine or Argentina or Kansas. All is pretty close to being fungible,like cash.