Thermolith S.A. started as a privately owned company, in 1998 in Kalyves, Northern Greece, for the production of basic unshaped refractories for the steel industry. In 1998, Themolith S.A. established a subsidiary company in the area of Skoumtsa, Grevena, in order to exploit mineral olivine, a refractory mineral used in the manufacturing of shaped and unshaped basic refractory products as well as slag conditioner and EBT filler sand in steel manufacturing.

    Soon, Thermolith S.A. was established in the Greek market as a reliable partner and a consistent producer of high quality olivine and refractory products. For more than a decade, the company served all Greek steel producers dominating the Greek market and exported 60% of its production to Europe, Balkan Countries and Africa, thanks to its proximity to Thessaloniki, the major logistics hub in Northern Greece.

    Through an extensive investment plan aiming at expanding into new markets, the company has increased its sales significantly in the last five years. In December 2011 Thermolith SA sold 70% of its shares to Aeiforos SA, member of the major industrial group in Greece VIOHALCO, which took over the management. After the acquisition, Thermolith SA has gained access to the know-how in crushing and screening technologies of the parent company Aeiforos SA which has a long and thorough experience in the production of aggregates, mortars and anthracite coal production. Moreover, through Aeiforos SA, Thermolith SA gained direct access to private bulk sea shipping facilities in Central Greece as well as benefits from multiple synergies in sales and logistics.

    As of 1.1.2020 the personel and activities of Thermolith S.A. are encorporated to those of Vitruvit S.A. thus achieving a faster growth rate and targeting to an even higher position at the global markets.


  • An olive colored silicate mineral

    An olive colored silicate mineral

  • A low cost product with exceptional qualities

    A low cost product with exceptional qualities

  • Olivine is a magnesium iron silicate mineral produced via thermo-flux from volcanic rocks. It is named after the olives, for its typically olive-green colour. The name olivine is used to indicate a group of orthosilicate minerals of the forsterite - fayalite solid solution series.

    It is a low cost source of MgO, with good insulating properties, high resistance to alkaline oxides that make it excellent for use in bricks and monolithic refractories. Because of its high melting point and resistance to chemical reagents is an important refractory material and thus can be used in interior protective lining of industrial furnaces and kilns.

    Olivine products are suitable for use as slag conditioner in the steel industry, EBT filler sand, sand blasting as well as foundry sand. Due to environmental policies promoting green-materials in recently years, Olivine has gained ground and largely replaced traditional materials.


EBT filler sand

EBT filler sand

Thermo Tap hole with optimised grain size distributions
Thermo Tap hole is produced from selected mineral olivine, a refractory mineral with high percentage of fosterite content and high refractoriness. As a result of long experience and cooperation with the steel making industry, we offer optimized grain size distributions that guarantee free and easy opening of the EBT in Electric Arc Furnaces. Standard production of EBT filler sand is 1-6mm, 2-6mm and 3-8mm.

Slag Conditioner

Slag Conditioner

Slag Conditioner with excellent artificial foamy slag
In electric arc furnace (EAF) applications, olivine when applied as a slag conditioner promotes the development of excellent artificial foamy slag and successfully balances viscosity and volume for efficient sulphur removal and electrode protection.
Olivine is more consistent in quality and aggregate size than calcined materials and shows uniform dissolution during a heat. Standard production of Thermo slag conditioner is 10-40mm.

Foundry Sand

Foundry Sand

Olivine Sand as Foundry Sand
Olivine is a valuable raw material for use in Foundries as Foundry sand for mould construction in both ferrous and non-ferrous metal casting.
Foundry sand from Olivine has an uniform low thermal expansion (0,8% at 1300 ˚C) resulting in better casting accuracy and smoother surface. Its high heat absorption and conductivity, along with its grain-shape that leads to optimal porosity, help degasing during casting. Olivine is compatible with non-organic binders such as Bentonite, demands small quantity of water and is suitable for use in alkaline resin-bonded system.
Furthermore, olivine not containing free silica, contributes to provide a high standard work environment for the workers and a high health and safety performance for the foundry.

Sandblasting sand

Sandblasting sand

Particularly suitable for wet-blasting abrasive systems.
Olivine is a dynamic natural mineral with high abrasion index. Having a hardness between 6.5 and 7.0 mohs, it is suitable for restoring aluminum, fiberglass, marble/stone facades and wood as well as cleaning and providing a medium profile on steel. It is particularly suitable for wet-blasting abrasive systems, creating an enhanced and high economy slurry blast mixture that leads to advanced performance. Olivine also has the advantage of reduced disposal concerns in some cases.


  • Suitable for gunning or ramming

    Suitable for gunning or ramming

  • for electric arc furnaces (EAF) and dry or wet tundish mixes.

    for electric arc furnaces (EAF) and dry or wet tundish mixes.

  • We specialize in the production of high-quality Magnesia and Magnesia/Olivine based unshaped refractory mixes suitable for gunning or ramming for EAF (Electric Arc Furnace).
    We also produce advanced dry or wet coating mixes for continuous-casting tundishes.

Wet coating tundish mixes

<b>Wet coating tundish mixes</b>

• Conventional tundish wear lining applied by wet spraying.
• Magnesia or magnesia-olivine containing mix.
• Use of organic fibers for improved dry-out.
• Thickness of wear lining with gunning mixes: 30-80 mm according to number of heats.
• Drying & preheating required.
• Requires very simple spraying machine.

Dry tundish mixes

<b>Dry tundish mixes</b>

• Magnesia or magnesia-olivine based mix.
• Organic or inorganic binders.
• No hydrogen pick-up since no water required.
• The dry mix powder can be poured without any special equipment.
• Requires a former with vibrating system and heating system for heating up to 200-250°C.
• Thickness of wear lining, 30-80 mm according to number of heats and the tundish volume.
• Curing with heating of the former
• It is possible to preheat up to 1200°C.

Cold setting tundish mixes

<b>Cold setting tundish mixes</b>

• Magnesia or magnesia-olivine mix+ inorganic binder.
• Special mixer and former needed.
• Highly-short curing (self-hardening] time at room temperature.
• Energy-saving application. No heating is needed.
• Better steel quality, less hydrogen pick-up.

Gunning and Ramming mixes for EAF lining repair

<b>Gunning and Ramming mixes for EAF lining repair</b>

• Magnesia or magnesia-olivine based mix
• Excellent adhesion on cold and hot linings.
• Excellent resistance to alkali attack and slag penetration.
• Improved resistance to thermal shock.


Quality Assurance

Quality Assurance

Quality assurance is one of our major concerns. Aiming to guarantee high and stable quality to our industrial clients, we have proceeded to the upgrade of the production lines, redesign of the production process with increased quality checks and corresponding training of our workforce.



We are committed to operate with absolute responsibility and respect for the environment and the society. Sound environmental management of production and storage installations is one of our most important targets and is absolutely essential to the sustainability of our activities. All employees must understand and adhere to our following environmental policy:

Environmental policy

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