Rune essence

Rune Essence is a free-to-play item on the OSRS Grand Exchange in the runes category.

In-game examine text: "An unimbued rune."

It has a Grand Exchange buy limit of 20,000 every four hours, a high alchemy value of 2 gp, and item ID 1436.

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Rune Essence shows an active flip setup with a margin of +1 gp and 295,312 trades over the last 24 hours.

At the buy limit of 20,000 every four hours, max profit per cycle is about 20.0k gp — high margin with healthy liquidity.