Limestone

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

In-game examine text: "Some limestone."

It has a Grand Exchange buy limit of 13,000 every four hours, a high alchemy value of 6 gp, and item ID 3211.

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Limestone currently has a flip margin of +0 gp, which isn't profitable to flip right now despite 3,787 trades over the last 24 hours.

Items with negative or zero margins like this are better watched than actively flipped until the spread widens.