Opal necklace

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

In-game examine text: "I wonder if this is valuable."

It has a Grand Exchange buy limit of 10,000 every four hours, a high alchemy value of 630 gp, and item ID 21090.

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Opal Necklace shows an active flip setup with a margin of +90 gp and 47,766 trades over the last 24 hours.

At the buy limit of 10,000 every four hours, max profit per cycle is about 900.0k gp — high margin with healthy liquidity.