Basalt fiber

Basalt fibers are produced by melt spinning a 1400 °C mass of molten basalt. The diameter of the resulting filaments is usually between 10-20 µm. Basalt fibers are mainly used in fiber-plastic composites, but also in areas such as filtration, horticulture and concrete reinforcement. In order to achieve a better bond to the plastic matrix in the field of fiber-reinforced materials, basalt fibers are often equipped with a silane sizing.

Pros and cons
Basalt fiber Properties


  • High tensile strength (higher than glass fibers)
  • Exceptional temperature resistance
  • Non-flammable
  • UV-stable
  • Natural product
  • High corrosion resistance
  • Low moisture absorption


  • High density (specific weight)
  • Not electrically conductive

Basalt fiber
Manufacturing process

After the raw basalt has been crushed and purified, it is melted at 1450 °C and, after pressing, drawn through nozzle holes to form filaments with a diameter of 10-20 µm. For better matrix adhesion, the filaments are additionally equipped with a silane sizing. In the subsequent process, the filaments are spun into yarn, combined into a roving or processed into short-cut fibers.

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technology and
quality of the fibre

State-of-the-art laboratory facilities, quality management according to ISO 9001:2015, energy management according to ISO 50001:2018 and last but not least the high demands on our own work ensure the high quality standards of our Basalt fiber. See for yourself.

If you want to know more about the technology and quality of our Basalt fiber If you want to know, just get in touch with us. We would be happy to advise you comprehensively and help you with our know-how.

You are looking for the perfect Basalt fiber for your application or have an exact requirement profile, which the used Basalt fiber must fulfill?

Then you are exactly right, as a technology leader in the field of fibre development and production, we offer you individual solutions and manufacturing processes that ensure constant and reproducible fibre quality.