JSP Sodium Metabisulfite (SMB) is a high-purity gold precipitant commonly used in the aqua regia refining process. This 16 oz (1 lb) bag contains 99% pure Na₂S₂O₅, widely used by refiners to recover dissolved gold from filtered aqua regia solutions.

Also known as SMB, sodium pyrosulfite, or disodium metabisulfite, this chemical is used during the precipitation stage of gold refining to convert dissolved gold back into solid metal.

Sodium metabisulfite is a standard refining chemical used by hobby refiners, jewelry recyclers, and precious metal recovery specialists.

Product Details

Purity: 99%
Chemical Formula: Na₂S₂O₅
Net Weight: 16 oz (1 lb)
Grade: Food / Photo Grade
Manufacturer: JSP Chem

Common Uses

Gold precipitation from aqua regia solutions
Precious metal recovery and refining
Scrap gold processing
Jewelry refining
Laboratory and refining applications

Typical Use

For gold precipitation:

Mix approximately 1 oz of sodium metabisulfite with 20–30 ml of water per ounce of dissolved metal in your aqua regia solution.

Add slowly while observing the reaction until gold precipitates from the solution.

Package Includes

(1) JSP 16 oz (1 lb) bag of Sodium Metabisulfite – Gold Precipitant

New to gold refining?

Visit our Gold Refining Learning Center for beginner-friendly guides that explain the basics of gold recovery, refining concepts, common materials found in electronics, and how precious metals are identified and evaluated.

These guides are designed to help you better understand refining processes and the tools commonly used in precious metal work.

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