Ancient essence

Ancient Essence is a members-only item on the OSRS Grand Exchange in the ores category.

In-game examine text: "Pure magical energy filled with a dark power."

It has a Grand Exchange buy limit of 300,000 every four hours, a high alchemy value of 16 gp, and item ID 27616.

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Ancient Essence shows an active flip setup with a margin of +1 gp and 86,015,616 trades over the last 24 hours.

At the buy limit of 300,000 every four hours, max profit per cycle is about 300.0k gp — high margin with healthy liquidity.