What is Dense Media Separation?

DMS Powders

What is Dense Media Separation?

During the process called Dense Media Separation (DMS), particles are largely separated according to their densities using gravity. A medium suspension of a given density is filled with particles with a variety of densities. Lighter than the medium density particles rise. These are referred to as ‘floats’. ‘Sinks’ are generally used to describe particles that are heavier than the mean density, causing them to sink to the bottom or sides of the tank. Dense Media Separation is therefore also commonly known as the sink-float method, or Gravity Separation Process.

Atomised FeSi: Coarse, Fine, Cyclone 60, Cyclone 40, DMS 70
Milled FeSi: 65D, 100D, 150D, 270D, 270F

DMS Powders

The use of Ferrosilicon in Dense Media Separation

Ferrosilicon is a powder-like substance that is used in the Dense Media Separation process. It is used to make the suspension in which the particles are submerged, by mixing it with water. Ferrosilicon possesses the ideal physical properties to achieve the optimal level of Stability, Viscosity and Density of the medium, to facilitate effective separation of the particles. Ferrosilicon is manufactured in various Grades, that differ in physical characteristics, in order to achieve different properties in suspensions.

DMS Powders – Producer of Ferrosilicon for Dense Media Separation

DMS Powders is a leading manufacturer and supplier of Ferrosilicon, producing an extensive range of quality Ferrosilicon powders for use in the Dense Media Separation of Diamonds. In diamond processing, Dense Media Separation is used to separate diamonds and other minerals from diamond-bearing material e.g. Kimberlite. The Kimberlite is submerged in the mixture, and will cause the heavier particles (diamonds) to separate from the lighter materials. 

This process is widely used in diamond plants across the world due to its effectiveness, cost-efficiency and ease of use. Ferrosilicon from DMS Powders is ideal for Dense Media Separation, and offers the following advantages:

  • Narrow particle size distribution results in predictable medium behaviour.
  • Excellent recovery due to the medium’s high magnetic susceptibility.
  • High medium specific gravity.
  • Low operating expenses because of the medium’s high specific gravity and magnetic recoverability.

DMS Powders manufacture the following Ferrosilicon products for Dense Media Separation:

  • Atomised FeSi – Coarse, Fine, Cyclone 60, Cyclone 40, DMS 70.
  • Milled FeSi – 65D, 100D, 150D, 270D, 270F.

Our packaging has been specifically designed for:
Ease of handling
Product integrity
Water resistance

125kg steel drums on pallets

250kg plastic drums on pallets

1mt & 2mt bags loose or on pallets

Supplier of Ferrosilicon for Dense Media Separation

Contact DMS Powders, leading Ferrosilicon supplier, to order the Ferrosilicon products you require for your Dense Media Separation process. A professional consultant will assist you to obtain the best Ferrosilicon for your application needs.

With a global customer base, you can rely on DMS Powders as the perfect partner and supplier of Ferrosilicon. Our professional service and quality products will ensure you get the best Ferrosilicon materials to of offer effective Dense Media Separation.

Contact DMS Powders today for assistance.

Let us answer all your Dense Media Separation Questions:

  1. What is Dense Media Separation (DMS)?

Dense Media Separation (DMS) is a physical separation process used in the mining and mineral processing industry to separate valuable minerals from gangue materials based on their differences in density. It involves immersing the ore or feed material in a dense medium (usually a heavy liquid suspension) and using the density contrast to achieve efficient separation.

  1. How does Dense Media Separation work?

Dense Media Separation relies on the principle that heavier materials will sink in the dense medium, while lighter materials will float. The dense medium, often a mixture of water and ferrosilicon or magnetite, has a specific gravity between that of the valuable minerals and waste materials. The feed material is introduced into the dense medium, and particles with different densities will separate by either sinking or floating. The separated fractions are then collected and processed further.

  1. What are the primary applications of Dense Media Separation?

Dense Media Separation is widely used in mineral processing for various applications, including:

  • Diamond mining: To separate diamonds from other minerals.
  • Coal preparation: For the separation of coal from impurities.
  • Base metal and precious metal ore processing: To recover valuable metals from ores.
  • Industrial minerals processing: For the separation of minerals like quartz, feldspar, and spodumene.
  • Recycling: To separate materials in recycling processes, such as the recovery of non-ferrous metals from scrap.


  1. What are the advantages of Dense Media Separation?

Dense Media Separation offers several advantages, including:

  • High efficiency in separating materials with different densities.
  • Effective removal of impurities from valuable minerals.
  • Applicability to a wide range of mineral types.
  • Versatility in controlling separation density by adjusting the dense medium composition.
  • Proven effectiveness in mineral processing operations for many decades.


  1. What are the limitations and challenges of Dense Media Separation?

Dense Media Separation has some limitations and challenges, including:

  • High operating costs due to the need for dense medium preparation and recycling.
  • Environmental concerns related to the disposal of dense medium and waste materials.
  • Limited applicability to materials with very fine or very coarse particle sizes.
  • The requirement for careful monitoring and control of the process to maintain separation efficiency.
  • Limited suitability for certain minerals or materials that have similar densities.

Dense Media Separation remains a valuable and widely used technique in the mineral processing industry, especially for ores with significant differences in density between valuable minerals and waste materials.

Dense Media Separation

Dense Media Separation

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