Guam tar

Guam Tar is a members-only item on the OSRS Grand Exchange in the other category.

In-game examine text: "A thick, foul-smelling, tar-like substance with a green tinge."

It has a Grand Exchange buy limit of 7,000 every four hours, a high alchemy value of 1 gp, and item ID 10142.

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Guam Tar shows an active flip setup with a margin of +6 gp and 511,112 trades over the last 24 hours.

At the buy limit of 7,000 every four hours, max profit per cycle is about 42.0k gp — high margin with healthy liquidity.