Black knife

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

In-game examine text: "A finely balanced throwing knife."

It has a Grand Exchange buy limit of 7,000 every four hours, a high alchemy value of 11 gp, and item ID 869.

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Black Knife shows an active flip setup with a margin of +30 gp and 136,097 trades over the last 24 hours.

At the buy limit of 7,000 every four hours, max profit per cycle is about 210.0k gp — high margin with healthy liquidity.