Crushed infernal shale

Crushed Infernal Shale is a members-only item on the OSRS Grand Exchange in the other category.

In-game examine text: "Speckled with smouldering rock."

It has a Grand Exchange buy limit of 25,000 every four hours, a high alchemy value of 48 gp, and item ID 30848.

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Crushed Infernal Shale shows an active flip setup with a margin of +274 gp and 957,107 trades over the last 24 hours.

At the buy limit of 25,000 every four hours, max profit per cycle is about 6.85m gp — high margin with healthy liquidity.