3 kg High-Purity Graphite Crucible for Electric Melting Furnaces

Melt and pour gold, silver, copper and other compatible nonferrous metals with this high-purity graphite crucible. Its tall cylindrical body is designed to fit compatible electric melting furnaces, while the molded pouring groove helps direct molten metal into an ingot mold or casting flask.

Graphite provides fast, even heat transfer and good resistance to thermal cycling when the crucible is heated, handled and stored correctly.

Key Features

• Nominal 3 kg crucible size

• High-purity graphite construction

• Designed for compatible electric melting furnaces

• Suitable for gold, silver, copper and compatible alloys

• Efficient thermal conductivity

• Low thermal expansion

• Molded pouring groove

• Tall cylindrical furnace-crucible design

• Suitable for refining, jewelry work and small foundry projects

• Smooth interior helps reduce retained metal

• Reusable with proper care

Specifications

• Product type: Furnace melting crucible

• Nominal size designation: 3 kg

• Material: High-purity graphite

• Overall height: Approximately 170 mm / 6.69″

• Top outside diameter: Approximately 75 mm / 2.95″

• Bottom outside diameter: Approximately 60 mm / 2.36″

• Inside diameter: Approximately 50 mm / 1.97″

• Approximate inside depth: 150 mm / 5.91″

• Maximum stated operating temperature: Approximately 1300°C / 2372°F

• Furnace compatibility: Properly sized electric melting furnaces

• Pouring feature: Molded pouring groove

• Color: Graphite black

Measurements are approximate. Confirm your furnace chamber, lifting-tong and pouring-tong dimensions before ordering.

Metal Compatibility

Suitable for melting compatible nonferrous metals and alloys, including:

• Gold

• Silver

• Copper

• Brass

• Aluminum

• Lead

• Precious-metal jewelry alloys

Compatibility depends on operating temperature, alloy composition, flux selection and furnace design.

Understanding the 3 kg Rating

The “3 kg” description identifies the crucible’s nominal commercial size. It does not mean the crucible will safely hold exactly three kilograms of every metal.

Gold, silver, copper and aluminum have very different densities. Actual working capacity also depends on the alloy, required headspace, furnace limitations and safe pouring practices.

Do not fill the crucible to the rim. Always leave adequate headspace to reduce the risk of spills and molten-metal overflow.

Package Includes

• One 3 kg-size high-purity graphite crucible

Electric furnace, furnace tongs, pouring tongs, flux, ingot molds, casting tools, protective equipment and metal are not included.

Ideal For

• Gold and silver melting

• Precious-metal refining

• Jewelry casting

• Copper and brass projects

• Pouring small ingots

• Laboratory and workshop metalwork

• Replacing a worn electric-furnace crucible

Furnace Compatibility

This crucible is intended for a compatible electric melting furnace with sufficient chamber height and diameter.

It is not recommended for direct torch heating, open-flame furnaces, charcoal kilns or carbon-fired furnaces. Direct flame exposure can accelerate oxidation, create uneven heating and cause premature cracking.

Do not assume compatibility based only on the furnace’s advertised kilogram rating. Compare the crucible’s complete external dimensions with the furnace chamber and lifting system.

Safe Use and Care

Graphite crucibles are durable but can crack from moisture, impact, oxidation or sudden temperature changes.

• Inspect the crucible before every melt.

• Do not use it if cracked, deeply eroded or structurally damaged.

• Keep the crucible completely dry.

• Store it away from moisture and corrosive chemicals.

• Preheat gradually according to the furnace manufacturer’s instructions.

• Never place wet metal, damp flux or contaminated scrap into a hot crucible.

• Use properly fitted lifting and pouring tongs.

• Avoid striking or dropping the crucible.

• Do not cool a hot crucible with water.

• Allow it to cool naturally in a protected, dry location.

• Use appropriate face, eye, hand, body and foot protection.

Important Safety Notice

Molten-metal work can cause severe burns, fire, toxic exposure and property damage. Operate the furnace only in a properly ventilated, fire-resistant workspace and follow the furnace, flux and alloy manufacturers’ instructions.

Never introduce sealed, hollow, wet, plated or unidentified material into molten metal. Moisture can expand explosively when exposed to molten metal.