Mineral Extractions
Mineral Separates for Geochronology and Isotopic Research featuring ELECTRIC-PULSE DISAGGREGATION
ODM has been performing mineral extractions from rock and sediment samples since 1974. Presently, ODM prepares close to 1500 research-grade mineral separates per year for domestic and international universities, analytical laboratories, governments, and mining/mineral exploration companies throughout the world. ODM has also become a world leader in utilizing Electric-Pulse Disaggregation (“EPD”) to provide clean and superior mineral separates.
Mineral Separates
ODM's full-service mineral processing laboratory prepares a wide range of mineral separates, including: zircon, apatite, monazite, feldspar, baddeleyite, sericite, illite, biotite, muscovite, hornblende, garnet, and sulphides.
We routinely tailor and modify our processing to: (1) meet our client’s specific requirements; and (2) optimize the quality of any given mineral extraction.
For most applications, a disaggregated sample (whether by EPD, mechanical crushing or sediments) is pre- concentrated on a shaking table to produce a low-grade table concentrate. Most zircon grains are very small (<50 μm) and are extracted from the table concentrate by micropanning. A zircon-rich pan concentrate is produced at this stage.
To extract other minerals, the table concentrate is typically refined by heavy liquid separation to produce a heavy mineral concentrate (“HMC”). The density of the heavy liquid can be modified to any specific gravity depending on the targeted mineral.
The quality of the mineral separates is monitored by experienced geologists/mineralogists and is confirmed by SEM/EDX analysis.
Electric-Pulse Disaggregation (“EPD”)
EPD is a comminution technique that uses high-voltage pulses to sunder a rock into its mineral constituents. An electric pulse travels through the rock along planes of weakness and creates extensional forces within the rock. ODM owns and operates a modified Spark-2 electric-pulse disaggregator.
There are many key features and advantages of EPD at ODM. For instance, ODM has strived to effectively eliminate carryover between samples:
• The disaggregation chamber comprises stainless steel and is completely accessible permitting it to be thoroughly cleaned before and after every sample.
• The EPD process occurs in water and does not generate airborne dust (a potential contaminant).
• The disaggregation chamber is lined with a new plastic sample bag for every sample. This ODM-exclusive development greatly reduces the risk of inter-sample contamination because both the sample material and the host water are contained within the sample bag giving a high-degree of confidence in the recovered minerals.
The EPD process liberates a higher proportion of undamaged, monomineralic grains compared to mechanical crushing. Typically, 0.5 to 2 kg of sample is usually sufficient for most mineral separate requirements.
The Spark-2 has a large disaggregation chamber that can accommodate samples up to 5 kg. Coarse mineral grains are not destroyed during EPD.
