Passing the Jinja bridge

This is a view from the bridge over the River Nile in Jinja, Uganda. We are en route to mining sites near Busia, Uganda.

Here are some key concepts related to modern and environmentally responsible gold prospecting methods that do not involve using mercury:

1. Gravity Separation: A method used for separating particles based on their specific gravity differences without the use of harmful chemicals like mercury.

2. Panning: The simplest form of placer mining, which involves washing soil or sediments in a pan to separate heavier gold from lighter materials by hand shaking and swirling motions.

3. Sluice Boxes (or Long Toms): A more efficient method than panning for separating heavy minerals like gold using water flow through riffles that trap the denser particles while allowing sand, gravel, clay, etc., to wash away.

4. Mercury-Free Gold Recovery: Refers specifically to techniques and technologies designed to extract gold without using mercury due to its toxic environmental impacts.

5. Refractory Ore Processing: Involves treating ores where precious metals are locked within sulfide minerals or other compounds that do not allow for easy extraction, often requiring more advanced processing methods like roasting or pressure oxidation instead of chemical leaching with harmful substances.

6. Biosorption and Bioremediation: Using biological processes to recover gold from ore without toxic chemicals; certain plants and microorganisms can accumulate heavy metals including gold in their tissues which are then harvested for extraction purposes.

These terms highlight methods that focus on sustainability, environmental protection, health safety of miners, as well as efficiency improvements over traditional mercury-based techniques.