An Ancient Method for Separating Gold from Impurities

Описание: An Ancient Method for Separating Gold from Impurities Using Vitriol, Rock Salt, and Ajur( brick red)
This method was used in the past to extract gold from rocks or gold-rich soil, whether the gold was in the form of very fine microscopic particles or small pieces.
Before starting the process, miners often ground the stones into a fine powder to make it easier for the gold to be released from within.
1. Preparing the Bottom Layer in the Pot
• A mixture is prepared from green vitriol (copper sulfate – CuSO₄), rock salt (natural sodium chloride, known in Morocco as “melha haya”), and ajur (crushed red bricks or heat-resistant clay).
• When heated, the vitriol decomposes and releases gases and oxides that attack metallic impurities.
• The rock salt helps form metal chlorides, making them easier to remove.
• The ajur acts as a heat-resistant barrier, preventing the gold from sticking to the bottom.
• This mixture is placed at the bottom of the pot, forming a layer about half-thick.
• On top of this layer, a thick sheet of paper is placed, followed by a thinner sheet, as an extra barrier.
2. Adding the Raw Gold
• On top of the papers, the medicine (a mixture that helps separate impurities) is added, followed by the raw gold or the soil/powder obtained from grinding the rocks.
• The pot is tightly sealed with a secure lid to prevent heat or materials from escaping.
3. Heating
• The pot is placed in a hot furnace or among burning charcoal.
• The high temperature causes the vitriol and salt to react with impurities, oxidizing them or turning them into compounds that melt or burn away.
• The lid is crucial, as it keeps the gold safe and prevents any loss or contamination.
4. Handling the Smoke
• If too much smoke appears during heating, a small amount of water is sprinkled to reduce it.
• The process continues until the impurities have fully decomposed and the reactions are complete.
5. Obtaining the Gold
• Once the process is finished, the pot is left to cool.
• The lid is carefully opened, and the remains of the medicine and ash are removed.
• Pure gold remains at the bottom, while the impurities either burn away or turn into separate ash.
📌 In summary:
This method relies on the chemical reaction between vitriol and rock salt under high heat, with ajur acting as an insulator and protector for the gold.
The result is the separation of pure gold from impurities — a process craftsmen used for centuries before the arrival of modern technology.