Cupellation Furnace

What Is a Cupellation Furnace?

The Cupellation Furnace is designed for the cupellation stage of fire assay analysis. During this process, lead buttons obtained after fusion are placed into cupels and exposed to controlled high temperatures.

As cupellation progresses, lead is oxidised and absorbed by the porous cupel. Precious metals such as gold and silver remain as a small metallic bead for subsequent weighing or analytical determination.

The LT-M1525 Cupellation Furnace is designed for intensive precious-metal laboratories and provides configurations for 50 or 100 cupels in a single furnace chamber.

Maximum Temperature up to 1200 °C

The furnace can reach a maximum operating temperature of 1200 °C. Silicon carbide heating elements provide the thermal energy required for high-temperature fire assay applications.

A K-type thermocouple continuously measures the furnace temperature. The Omron temperature controller allows the operator to monitor and adjust the target value during operation.

Stable temperature conditions are particularly important during cupellation because consistent heating helps create comparable operating conditions across multiple samples.

50 or 100 Cupel Capacity

The LT-M1525 is available with furnace chamber configurations designed to accommodate 50 or 100 cupels.

This capacity supports laboratories processing large numbers of fire assay samples. Multiple cupels can be handled within the same heating cycle, which reduces repeated furnace loading and helps improve daily laboratory throughput.

The exact cupel size and internal loading arrangement should be confirmed according to the selected furnace configuration before ordering.

Silicon Carbide Heating System

The furnace uses silicon carbide heating elements. These elements are suitable for high-temperature furnace applications and provide controlled heat transfer to the furnace chamber.

The internal furnace construction also incorporates refractory materials designed to withstand demanding thermal conditions. Liya Test describes the furnace chamber as modular, which simplifies maintenance and replacement of internal components when required.

Heavy-Duty Laboratory Construction

The LT-M1525 is manufactured with a robust carbon-steel body for intensive laboratory operation. Its external dimensions are approximately 105 × 145 × 170 cm, while the complete furnace weighs approximately 620 kg.

Due to its size and weight, laboratories should prepare a suitable installation area with adequate floor capacity and sufficient clearance for loading, maintenance and ventilation.

Fire Assay Laboratory Safety

Cupellation can generate lead-containing fumes, particularly when the furnace door is opened. Effective local exhaust ventilation is therefore important around fire assay furnaces.

NIOSH documentation from mine assay laboratories describes dedicated exhaust hoods positioned above cupellation furnaces, with exhaust air discharged outside the laboratory to capture fumes during furnace operation and door opening.

Overall, the LT-M1525 Cupellation Furnace combines 1200 °C maximum temperature, 50 or 100 cupel capacity, silicon carbide heating, precise temperature monitoring and heavy-duty construction. It provides a practical solution for gold, silver and precious-metal fire assay laboratories requiring controlled and repeatable cupellation conditions.