Black pickaxe

Black Pickaxe is a free-to-play item on the OSRS Grand Exchange in the weapons category.

In-game examine text: "Used for mining."

It has a Grand Exchange buy limit of 4 every four hours, a high alchemy value of 87 gp, and item ID 12297.

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Black Pickaxe shows an active flip setup with a margin of +950 gp and 1,033 trades over the last 24 hours.

At the buy limit of 4 every four hours, max profit per cycle is about 3.8k gp — high margin with healthy liquidity.