Granite longsword

Granite Longsword is a members-only item on the OSRS Grand Exchange in the weapons category.

In-game examine text: "A razor sharp longsword made of stone."

It has a Grand Exchange buy limit of 70 every four hours, a high alchemy value of 19.2k gp, and item ID 21646.

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Granite Longsword shows an active flip setup with a margin of +2.7k gp and 569 trades over the last 24 hours.

At the buy limit of 70 every four hours, max profit per cycle is about 191.5k gp — high margin with healthy liquidity.