Chemical analysis

Gold and silver purity testing via cupellation method

RAFINOR uses the cupellation method, one of the most precise and respected traditional techniques for analyzing precious metals. This method, which dates back to Antiquity, was widely used by Asian civilizations as early as 3000 BC, with documented use in Mesopotamia, India, and later in ancient Greece and Rome.

Cupellation separates gold and silver from impurities through a high-temperature heating process in a special furnace. The cupel, a porous and absorbent vessel, draws in and retains base metals such as lead, copper, or zinc, leaving behind only the noble metal in its pure form.

Although millennia old, this technique is still used today due to its exceptional accuracy and is recognized as a benchmark standard in the refining and evaluation of precious metals.

How does cupellation work?

The process begins with placing the metal sample into a cupel and inserting it into a special furnace. The base metals are oxidized and absorbed, while gold and silver remain in their pure form. This technique is standardized and used in prestigious laboratories worldwide, known for its high accuracy results.

Advantages of the cupellation method

• High precision – completely removes impurities, providing exact results on gold and silver composition.
• International reliability – a globally used method in refineries and testing laboratories.
• Efficiency and safety – does not require aggressive chemical reagents, ensuring a controlled and eco-friendly process.

The analysis process at RAFINOR

1. Receiving and registering the sample – each sample is identified and labeled for tracking.
2. Sample preparation – may include weighing, splitting, or adding auxiliary substances to facilitate analysis.
3. Melting and impurity separation – the metal is heated in the cupel at high temperatures, removing base metals.
4. Cooling and recovery of pure metal – gold and silver remain in pure form and are prepared for final testing.
5. Final analysis and certification – detailed analysis reports are issued, in compliance with international standards.

Why choose RAFINOR?

RAFINOR guarantees precision and transparency in the evaluation of precious metals, using modern equipment and internationally recognized testing methods. Contact us for an accurate and secure verification of your gold and silver purity!