Giving you advanced testing and consultation services for mineral projects around the world

FLSmidthʼs Dawson Metallurgical Laboratories provide metallurgical testing for ore amenability, process development, flowsheet layout, plant design, and plant surveys. We analyse new and existing ore bodies and flowsheets to optimise grade and recovery, improving your productivity.


The FLSmidth Dawson Metallurgical Lab is a world leader in flotation testing and flowsheet design. We offer testing services in most chemical and physical processing applications, including:


  • Flotation
  • Hydrometallurgical applications
  • Gravity separation
  • Magnetic separation
  • Size classification


Flotation concentration 

We have extensive experience with different mineral separation procedures, including sulphide ores, oxide or transition ores and industrial minerals. We use bulk sulphide flotation tests to recover precious metals associated with pyrite or other sulphides. We can also incorporate gravity pre-concentration and magnetic separation into any test program. Selective flotation tests include: copper-molybdenum, copper-gold, molybdenum-talc, copper-lead-zinc-pyrite, silver-lead-zinc-pyrite, silver from sulfosalts, enargite-pyrite, lead zinc-pyrrhotite, nickel-pyrrhotite, cobalt-pyrrhotite, and iron ore processing.


Bench scale flotation tests target the recovery of industrial minerals such as cassiterite, potash, phosphates, talc, silica “frac” sands, silicates and barite; and energy minerals such as coal, resin-coal and tar sands.


Process development tests generally apply test series to establish the primary grind size, reagents, residence time and cleaner (regrind) requirements to characterise ore response. Locked cycle tests recirculate water and intermediate products to simulate closed-circuit process operation.


Hydrometallurgical testing 

The dissolution of metals in cyanide or acid may be the most effective method to recover metals from an ore. Lab stirred vessels, bottle roll, and leach column testing provide design criteria needed to design and operate a hydrometallurgical circuit. Preoxidation may be necessary to expose the metals to the leach solution. Rapid oxidative leaching (ROL) and Parr autoclave testing improve metal extraction of refractory material.



  • Cyanidation (CIP, CIL, CIC)
  • Pressure/oxidation leach
  • Bottle rolls
  • Mixed reactor
  • Column leach
  • Chemical oxidation
  • Gold and copper diagnostic leach


Gravity concentration testing 

When the specific gravity of the desirable minerals is sufficiently different than the gangue mineral, we recommend our customers consider gravity separation. Gravity separation equipment will reliably test the amenability of the ore to gravity concentration, and we offer a dedicated suite of gravity equipment and personnel with extensive experience for this purpose.


Gravity concentration 

  • Knelson bowl
  • Deister table
  • Mozley table
  • Gemini table
  • Duplex jig
  • REFLUX™ Classifier

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