Silver bar

Silver Bar is a free-to-play item on the OSRS Grand Exchange in the bars category.

In-game examine text: "It's a bar of silver."

It has a Grand Exchange buy limit of 10,000 every four hours, a high alchemy value of 90 gp, and item ID 2355.

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Silver Bar shows an active flip setup with a margin of +4 gp and 334,009 trades over the last 24 hours.

At the buy limit of 10,000 every four hours, max profit per cycle is about 40.0k gp — high margin with healthy liquidity.