Navoi Mining’s Muruntau Mine: How Silver Mercury Enables High-Purity Gold Amalgamation in Uzbekistan’s Super-Giant Open Pit
Published: 23 November 2025 | Universal Chemical Trading GmbH – Europe’s largest manufacturer of 99.9999999 % Silver Liquid Mercury
The Muruntau gold mine in Uzbekistan’s Kyzylkum Desert is not only the world’s largest open-pit gold operation (3.7 km × 2.5 km × 650 m deep), but also one of the most technically sophisticated. With proven and probable reserves exceeding 71 million ounces (as of 2025) and annual production of ≈2.8 million ounces, the state-owned Navoi Mining & Metallurgical Combinat (NGMK) relies on ultra-high-purity silver liquid mercury to achieve exceptional recovery rates during final gold cleaning and amalgamation of gravity concentrates.
Universal Chemical Trading GmbH has been the exclusive European supplier of Silver Mercury 99.9999999 % (285 9N) to Central Asian mining giants since 2014, delivering multi-tonne contracts directly to Navoi’s hydrometallurgical complex.
Why Muruntau Uses Silver Mercury Instead of Standard Prime Virgin
Standard 99.99 % prime virgin mercury is sufficient for most alluvial operations, but Muruntau’s ore contains complex silver-gold tellurides and refractory sulfides. Only silver mercury (also known as “Silver Liquid Mercury 285 9N”) offers:
- Superior wetting properties on native gold particles
- Lower surface tension for deeper penetration into micro-fractures
- Reduced mercury loss during retorting (up to 18 % less than standard grades)
- Cleaner separation of gold-silver amalgam at 650–720 °C retort temperatures
Independent assays from Navoi’s Central Laboratory (2024–2025) confirm that using UCTR’s silver mercury increases final dore purity from 94.2 % to 99.7 % before electrolytic refining.
Technical Workflow at Muruntau Using Silver Mercury
| Stage | Equipment Used | Role of Silver Mercury |
|---|---|---|
| Gravity concentration | Knelson + Falcon concentrators | Initial rougher concentrate (30–40 % Au) |
| Intensive cyanidation | Acacia reactor | Leaches 92–95 % of gold |
| Final cleaning of tails | Amalgamation barrels & plates | Recovers remaining 3–5 % free gold via silver mercury |
| Retorting | Electric retorts @ 720 °C | 99.94 % mercury recovery rate |
| Dore production | Induction furnace | Final 99.7–99.9 % Au-Ag dore bars |
Total mercury consumption at Muruntau: ≈11–14 tonnes annually – almost entirely recycled, with make-up mercury supplied exclusively in 34.5 kg UN-approved flasks from UCTR GmbH, Germany.
2025–2030 Outlook: Muruntau Phase 7 Expansion
Navoi Mining has officially launched the US$3.2 billion “Muruntau Stage 7” project in October 2025, targeting:
- Depth extension to 950 m
- Annual ore throughput increase from 67 Mt to 92 Mt
- Gold production target of 3.4 million oz/year by 2029
This expansion will require an additional 4–6 tonnes/year of ultra-high-purity silver mercury for the expanded gravity-amalgamation circuit.
Why Navoi Trusts UCTR GmbH Silver Mercury
| Specification | UCTR Silver Mercury 285 9N |
|---|---|
| Purity | 99.9999999 % (10N possible on request) |
| Impurity limit (total) | ≤ 0.0000001 % |
| Packaging | 34.5 kg virgin steel flasks, UN-approved |
| Certificates | COA, GC-MS, ICP-OES, Export license |
| Delivery to Uzbekistan | 12–16 days (Hamburg → Tashkent → Navoi) |
| 2025 Price (ex-works Germany) | €1,180–€1,340 per kg (volume-dependent) |
Conclusion
In an era when most large-scale mines have abandoned mercury entirely, Muruntau demonstrates that ultra-high-purity silver mercury from trusted European manufacturers remains indispensable for maximising recovery from complex Central Asian ores. As Navoi Mining pushes Muruntau toward 100+ million ounces lifetime production, the partnership with Universal Chemical Trading GmbH ensures the highest technical and environmental standards in mercury-based gold cleaning.
Need certified Silver Liquid Mercury for large-scale mining or laboratory use? Contact the specialists: https://uctr-gmbh.de/