Marlin

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

In-game examine text: "Some nicely cooked marlin."

It has a Grand Exchange buy limit of 10,000 every four hours, a high alchemy value of 102 gp, and item ID 32352.

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Marlin shows an active flip setup with a margin of +61 gp and 436,040 trades over the last 24 hours.

At the buy limit of 10,000 every four hours, max profit per cycle is about 610.0k gp — high margin with healthy liquidity.