Opal ring

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

In-game examine text: "A valuable ring."

It has a Grand Exchange buy limit of 10,000 every four hours, a high alchemy value of 630 gp, and item ID 21081.

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Opal Ring shows an active flip setup with a margin of +113 gp and 64,156 trades over the last 24 hours.

At the buy limit of 10,000 every four hours, max profit per cycle is about 1.13m gp — high margin with healthy liquidity.