Stainless Steel Alum Cup

Dissolve glassified borax flux, remove firescale, and clean soldered gold and silver pieces quickly at the bench. The Stainless Steel Alum Pickling Cup is a heat-resistant bench container designed for post-soldering chemical cleaning. Jewelers mix powdered alum with water directly inside the cup and heat it with a microtorch or alcohol lamp. Boiling the solution strips away stubborn glassy borax flux and surface oxidation without generating toxic acid fumes.

Formed from polished stainless steel, this cup resists hot alum solutions and will not contaminate pickle baths. The integrated pedestal base elevates the boiling basin above your soldering pad, keeping table surfaces safe while providing a stable, tip-resistant footing. Available in three nesting sizes—Small (Ø45 mm), Medium (Ø70 mm), and Large (Ø95 mm)—it covers everything from individual prong settings to wide cuffs and heavy chains.

Why Choose the Stainless Steel Alum Boiling Cup

• Fast Borax Flux & Oxide Dissolution: Simmering an alum solution inside this cup rapidly dissolves hardened borax flux glazes and surface blackened firescale on freshly soldered precious metal jewelry.

• Corrosion-Resistant Stainless Steel Alloy: Heavy-gauge stainless steel resists pitting and chemical attack from boiling alum solutions, ensuring long shop life without contaminating metalwork.

• Stable Pedestal Foot Base: The flared pedestal base prevents accidental tip-overs during active boiling and keeps radiant heat off your workbench top.

• Direct Flame Safe: Engineered to sit directly over an open microtorch or alcohol burner flame for rapid, on-demand heating at the soldering bench.

• Non-Toxic Pickling Alternative: Provides a safer workshop environment by utilizing mild potassium alum instead of hazardous sulfuric or sodium bisulfate acid baths.

• Space-Saving Nesting Storage: All three cup sizes nest neatly inside one another, minimizing storage space on crowded jewelry benches.