DMS in Diamond Processing – DMS Powders

DMS Powders

DMS in Diamond Processing: Precision Separation That Protects Value


Diamond recovery is a game of accuracy. Lose density control or consistency for even a short period, and valuable stones can slip through the system unnoticed. That’s why DMS in diamond processing remains a cornerstone of modern recovery plants. When properly managed, it delivers clean separation, high recovery rates, and predictable results across varying ore types.

At the centre of this process is the dense medium itself, typically a ferrosilicon-based slurry, carefully controlled to separate diamonds from waste rock based on density differences. DMS Powders specialise in producing the precise ferrosilicon grades required to keep these systems running efficiently and consistently.

Contact the leading producers of Ferrosilicon today for more information about our Milled Ferrosilicon range, or read more below about the uses and application thereof.

 

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

DMS Powders:

What Is DMS in Diamond Processing?


Dense Media Separation (DMS) is a gravity-based process that separates materials according to their relative densities. In diamond processing, it is used to concentrate diamond-bearing material before final recovery stages such as X-ray sorting.

The process works by immersing crushed ore into a dense medium slurry. This slurry is calibrated to a specific density:

  • Lighter waste rock floats
  • Heavier diamond-bearing material sinks

This separation allows operators to discard a large portion of waste early in the process, significantly improving efficiency downstream.

For a deeper technical overview of how this works in practice, see dense media separation of diamonds.

DMS Powders

What We Stand For

Our Vision
DMS Powders will continue to be a world class market leader in the production, distribution and marketing of dense media ferrosilicon powders.
Our Mission Elements
  • Profitably maintain our core business through excellence in production, distribution and marketing.
  • Develop and enhance global alliances and external relationships to secure optimal market knowledge and increase strategic and operational flexibility.
  • Empower employees with knowledge and resources to act in accordance with core values.
  • Create industry benefit by providing opportunities for shared technical knowledge and skills.
  • Actively manage and build our portfolio of high-quality assets and services.
  • Continue the drive towards a high-performance organisation, in which every individual accepts responsibility and is rewarded for results.
  • Earn the trust of employees, customers, suppliers, communities and shareholders by being forthright in our communications and consistently delivering on commitments.
Our Values
  • Ethics: Uncompromising honesty, integrity, trust and reliability in our dealings with each other.
  • Excellence: Setting high standards in every aspect of business and continuously striving to outperform them.
  • Prosperity: Pursuance of productivity and effectiveness to create a fair value proposition for shareholders, customers, employees and suppliers.
  • Sustainability: An overriding commitment to safety, environmental responsibility and sustainable development.
Key Principles
Automised FeSi

Coarse, Fine, Cyclone 60, Cyclone 40, DMS 70

Milled FeSi

65D, 100D, 150D, 270D, 270F

DMS Powders

Packaging


Our packaging has been specifically designed for:

Ease of handling

Safety

Product integrity

Durability

Water resistance

Why DMS Is Still Critical in Diamond Recovery

Despite advances in sensor-based sorting, DMS remains essential for several practical reasons:

1. Early Waste Rejection

Removing low-density waste early reduces the load on downstream recovery equipment, cutting operational costs.

2. Consistent Feed Preparation

DMS delivers a more uniform feed to X-ray and grease tables, improving recovery accuracy.

3. Scalability Across Operations

From large-scale kimberlite mines to smaller alluvial operations, DMS adapts well to different processing environments.

4. Proven Reliability

This isn’t a new or experimental process. It has been refined over decades and remains one of the most dependable methods in diamond beneficiation.

The Role of Ferrosilicon in DMS

The performance of any DMS plant comes down to the quality of the dense medium. Ferrosilicon is the material of choice because of its high density and magnetic properties, which allow for easy recovery and reuse.

A well-formulated ferrosilicon medium provides:

  • Stable and accurate density control
  • Low viscosity for better separation efficiency
  • Minimal contamination and degradation
  • High recovery rates through magnetic separation

DMS Powders manufactures a range of ferrosilicon products designed specifically for dense media applications. You can view available options on our ferrosilicon product range page.

How Density Control Affects Diamond Recovery

In DMS diamond circuits, density isn’t just a setting, it’s a critical control point that directly impacts recovery.

If the density is too low:

  • Diamonds may report to the float fraction and be lost

If the density is too high:

  • Excess waste material sinks, reducing efficiency and increasing downstream load

Maintaining the correct cut-point density ensures that diamonds consistently report to the sink fraction without unnecessary contamination.

Operators typically monitor:

  • Medium density (via densimeters)
  • Viscosity
  • Magnetic recovery efficiency
  • Ferrosilicon consumption rates

Even small deviations can lead to measurable losses, especially in high-throughput plants.

Challenges in DMS Diamond Processing

While the process itself is well established, maintaining optimal performance comes with its own set of challenges.

Medium Stability

Poor-quality ferrosilicon can lead to instability in the slurry, affecting separation accuracy.

Contamination

Clays, fines, and organic material can interfere with medium behaviour and density control.

Wear and Degradation

Over time, ferrosilicon particles can break down, altering their density characteristics.

 Recovery Losses

Inefficient magnetic recovery systems can result in ferrosilicon loss, increasing operating costs.

Addressing these challenges starts with selecting the right supplier and product. Working with experienced ferrosilicon manufacturers such as ferrosilicon suppliers in Africa ensures consistent quality and technical support.

Best Practices for Optimising DMS Performance

Operators who get the most out of their DMS circuits tend to focus on a few key areas:

Maintain Consistent Feed Preparation

  • Ensure proper crushing and screening
  • Avoid excessive fines entering the circuit

Monitor Medium Quality Closely

  • Regularly test density and viscosity
  • Replace degraded ferrosilicon when needed

Optimise Magnetic Recovery

  • Keep magnetic separators well-maintained
  • Minimise losses of ferrosilicon

Control Water Quality

  • Poor water quality can affect slurry stability
  • Manage contaminants entering the system

Use the Right Ferrosilicon Grade

Different applications require different particle sizes and densities. Choosing the correct grade makes a noticeable difference in performance.

For answers to common technical questions around ferrosilicon use, visit the ferrosilicon FAQ section

DMS Across Different Diamond Deposits

Not all diamond deposits behave the same, and DMS circuits often need to be adjusted accordingly.

Kimberlite Deposits

  • Require careful crushing to liberate diamonds without damage
  • DMS helps concentrate material before final recovery

Alluvial Deposits

  • Often contain more variable feed material
  • DMS assists in stabilising the process despite fluctuations

Tailings Retreatment

  • DMS can recover diamonds missed in earlier processing
  • Particularly useful where historical inefficiencies existed

Each application places slightly different demands on the dense medium, reinforcing the importance of a consistent, high-quality ferrosilicon supply.

The Link Between Ferrosilicon Quality and Plant Profitability

There’s a direct connection between ferrosilicon quality and the bottom line of a diamond operation.

Higher-quality ferrosilicon typically results in:

  • Better separation accuracy
  • Lower consumption rates
  • Reduced maintenance issues
  • Improved recovery efficiency

Lower-quality material, on the other hand, often leads to:

  • Increased losses
  • Frequent density adjustments
  • Higher operating costs

Over time, these differences add up, especially in large-scale operations processing thousands of tonnes per day.

Partnering With the Right Supplier

DMS is not just about equipment. It’s about consistency across the entire process. Reliable supply, technical support, and product quality all play a role in keeping operations stable.

DMS Powders has built a reputation in the industry for supplying ferrosilicon tailored to dense media applications. Our focus on particle size distribution, durability, and magnetic properties ensures that operators can maintain tight control over their DMS circuits.

Speak to a Specialist About Your DMS Requirements

If you’re running a diamond processing plant or planning a new operation, it’s worth reviewing how your DMS circuit is performing. Small adjustments in medium quality or density control can make a noticeable difference in recovery and operating costs.

Contact DMS Powdersto learn more about our solutions, or explore our detailed resources on DMS in diamond processing. Whether you need the right ferrosilicon grade, technical guidance, or a reliable supply partner, our team can assist in keeping your operation efficient and consistent.