Wyvern bones

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

In-game examine text: "Bones of a large flying creature!"

It has a Grand Exchange buy limit of 7,500 every four hours, a high alchemy value of 96 gp, and item ID 6812.

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Wyvern Bones shows an active flip setup with a margin of +109 gp and 105,023 trades over the last 24 hours.

At the buy limit of 7,500 every four hours, max profit per cycle is about 817.5k gp — high margin with healthy liquidity.