Olivine is a mineral that can be found in Universe in many forms, with multiple application, both in industry and jewellery making, where it is highly appreciated as a gemstone for its wonderful hues of translucent greens and a rich symbolism, considering its both terrestrial and extra-terrestrial origin: (1) olivine is one of the first minerals that crystallizes in the melted magma that is rich in magnesium and low in silica, such as Gabbro, Peridot, Basalt and Dunite; (2) olivine has also been discovered in meteorites which are thought to have originated from the mantle of a rocky planet that sometime orbited between Mars and Jupiter, or it might have originated from an asteroid large enough to have developed an internal differentiated structure consisting of a rock mantle and a metallic core; (3) further, a “rain” of small crystals of olivine was identified by NASA in the dusty cloud of a developing star, when the strong air currents lifted the particles from the surface of the developing star into the atmosphere, and then dropped them when the currents lost their momentum.
Olivine, also called Peridot is not only an aesthetic gemstone, but also a mineral that is largely used in industry due to its physical characteristics and chemical composition. Traditionally, olivine is used as refractory material, slag conditioning, blasting media and foundry sand. When the reactivity of olivine’s surface is enhanced, it has many new applications, such as a neutralizer for sulphuric acid, a heavy metal adsorbent, a catalyst for decomposing toxic organic chemicals, a magnesium source for soil improvement in agriculture, and an additive in water treatment. Most recently, olivine, especially forsterite, is recognized as one of the most promising feedstock in CO2 sequestration by mineral carbonation.
In foundries, olivine is an economic alternative for dolomite in steel casting; also, it is used for a precise control of basicity index of the formation mixture and conditioning of furnace slag. Olivine has a higher MgO content of approx. 50% than dolomite, therefore less quantity of additive is necessary to be added into the furnace to reach the required Mg concentration of the molten metal, which means lower production costs and higher efficiency to meet the quality standards in metallurgical industry.
Highly refractory with a very high melting point of approx. 1780 °C are essential for using olivine as taphole filler in an electric arc furnace with Eccentric bottom tapping (EBT). The molten metal should be hold in furnace bay until it reaches its full temperature, when the nozzle is opened allowing the metal to flow. A very tough material is necessary to fill the nozzle to avoid slag problems. Precise dimensions, shape and angular configuration of Olivine particles provide compaction properties which resist metal penetration into the nozzle. When the molten metal reaches its optimum consistency, the nozzle is opened and olivine pops through, allowing metal to flow into the pot.
With high thermal resistance and chemical stability, olivine is well suited as molding sand for metal casting, in certain metal works such as manganese steel, brass, bronze and aluminum. Olivine sand is easy to work with and can be recycled and re-used without difficulty. It produces a clean surface which requires a minimum amount of finishing.
As a blasting material, olivine is distinguished by its ability to quickly clean surfaces, generating an insignificant amount of dust. It is an ecologic and non-toxic material, widely recommended for outdoor blasting, to remove rust, old paint coatings and mill scale. Olivine particles are angular and sub-angular, with a dimension that varies between 20 and 120 Mesh, with hardness between 6.5 and 7.5 Mohs, and a bulk density of approx. 3,2 g/cm3. Among other blasting media, olivine is considered superior to dolomite and a competitive product among slag-based abrasives like copper slag and nickel slag.
GritSablare is a national leader in the field of blasting and metallic and non-metallic surface preparation, providing a wide range of blasting media, such as: olivine – sole distributor in Romania, steel grit, steel shots, stainless steel grit, stainless steel shots, white fused aluminium oxide (white electrocorundum), brown fused aluminium oxide (brown electrocorundum), glass beads, red garnet, copper slag, and also, professional blasting equipment: blasting cabinets, outdoor blasting installations, blasting rooms, private protective equipment and blasting accessories of highest quality.