Rock Types

Basalt Ballast

Basalt ballast are common aphanitic igneous extrusive rocks composed of minute grains of plagioclase feldspar (labradorite), pyroxene, olivine, biotite, hornblende, and less than 20% quartz. Basalt is dark grey rock which varies from almost featureless to spotted. Basalt is a herd black volcanic rock which is the most common type in the earth’s crust. Depending on how it is erupted, basalt can be hard and massive or crumbly and full of bubbles.

Beaches underlain by basalt usually include a variety, some with spots, and some that are uniformly gray. Basalt have bubbly flow tops, and these fill with a variety of colored minerals. Basalt ballast meets rail ballast specifications and provides effective stability. Basalt is a main line today as it can stand up to grinding action of passing trains without producing too many fine particles that could clog things up.


  • Ophitic basalt or Ophite is rare and comes from the flow interior and has uniform spots which are usually lighter and harder than the rest of the rock.
  • Pegmatoid pegmatitic basalt o dolerite is also very rare and is from the flow interior and has white crystals which are conspicuous.


  • Basalt rock is great for paths under bricks or paves also.
  • Basalt has superior thermal and acoustic properties in rock wool insulation
  • Higher than average strength in specialty applications
  • Use on railroad for ballast


  • Basalt is excellent for railroad track ballast because of its insensitivity to chemical influences, resistance to mechanical stress, high dry relative density, frost resistance, and sea water resistance
  • Basalt is among the hardest form of rock and according to the Moh’s scale in the US, basalt is ranked 8-9 and categorized as critically hard. In addition to its natural firmness, it also has a high modulus of elasticity, and is considered extremely durable and can withstand even the toughest weather conditions. Thanks to its hardness and durability, basalt has become a favorite for railroaders, landscapers and modelers.
  • Because of its high modulus of elasticity, basalt is ideal for high-strength applications. It is also naturally fire-resistant making it also ideal for high temperature applications.


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PROFI Ballast “Basaltic Rock”. 

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Other Rocks

Basalt Ballast
Basalt Ballast