Exploration of a new Olivine Deposit in Northen Greece

Mining has been rooted in the Greek economy since ancient times. Today, the mining industry remains one of the most vital and important contributors to the Greek economy, employment and exports. Companies in Greece export roughly two-thirds of their production. The principal export products of the Greek mining industry are bentonite, perlite, caustic and deadburned magnesia, alumina, aluminium, bauxite, nickel, pumice and marble.

Moreover, Greece has significant deposits of clay, limestone, slate, gypsum, kaolin, mixed sulphate ores (zinc, lead), olivine, talc, zeolite, pozzolan and quartz among others. There are also significant mineral deposits which have not been exploited, or where exploration has temporarily ceased, such as, chromite, uranium, gold, oil, emery and salt.

The extractive industries in Greece have become proactive in sustainable development policies and are now acting to prevent and restore environmental degradation. In 2003, during the 14th Annual General Meeting of the Society of Mining Professors and the First International Conference on Sustainable Development Indicators in the Minerals industry held on the island of Milos in Greece, the Society issued the Milos Statement, detailing the contribution of the minerals professional community to sustainable development.

One of the minerals that have been exploited during the last decade in Greece is olivine. Olivine is a magnesium iron silicate with the formula (Mg, Fe)2SiO4. It is a common mineral in the Earth’s subsurface but weathers quickly on the surface. Olivine is named for its typically olive-green color, though it may alter to a reddish color from the oxidation of iron.

The melting point is high, between 1780 and 1810o C. The specific weight is 2,8 to 3,2 tn/m3. Due to the fact that there are no toxic substances of free silica; olivine is one of the friendliest, environmental-wise, minerals. It is classified by the American Environmental Committee as a ‘non dusting’ mineral.

Today the main identified deposits of olivine in Greece are in the Vourino Mountain range in Western Macedonia, in Northern Euboea and in the central mainland. The new deposit that Grecian Magnesite intends to exploit is near the village of Chromio in Western Macedonia. The area of the deposit is about 400 x 250 meters. The deposit has a volume of 8,3 million cubic meters which corresponds to possible resources of 23,3 million tones of olivine.

Based on a systematic sampling campaign the quality is characterized as healthy olivine. The presence of chromites adds value to olivine due to its refractory properties. A representative chemical analysis of the deposit is of the following chemistry;

SiO2

46,50 – 48,30%

CaO

0,15 – 1,30%

Fe2O3

7,15 – 9,90%

MgO

45,30 – 48,00%

Cr2O3

0,20 – 1,80%

L.O.I

0,20 – 1,30%

The mine which is planned to operate will be a modern Open Pit Mine. Initially, Grecian Magnesite is planning to invest in the improvement of the infrastructure and after that the construction of the necessary facilities to start production and then the actual opening of the production benches.

The exploitation of the deposit will follow the modern rules and regulations of open pit mines. At the end of the exploitation of each bench, the width will be reduced for environmental rehabilitation according to the Environmental Rehabilitation Design.

Currently, the most important uses of olivine are:

  • As a slag conditioner and a refractory in the steel industry. In the refractory industry it can be used as block olivine for furnace linings, ladle linings, patching compounds, crushed olivine mixed with a binder for refractory masses and bricks.
  • As a cost-effective raw material for the production of magnesium metal. This can be possible if the cost of silica produced be comparably similar to the cost of the fumes of silica.
  • As an ornament stone because of its beautiful olive green color. They are especially extracted for making jewelry.

In addition, a worldwide search is on for cheap processes to sequester CO2 by mineral reactions. Removal by reaction with olivine is an attractive option, because it is widely available and reacts easily with the acid (CO2) from the atmosphere. When olivine is crushed, it weathers completely within a few years, depending on the grain size. All the CO2 that is produced by burning one liter of oil can be sequestered by less than one liter of olivine. The reaction is exothermic but slow.

Grecian Magnesite is a privately owned company established in 1959 and a magnesia expert. The company produces and commercializes some 200,000 tpa of Caustic Calcined magnesia, Deadburned (Sintered) magnesia, Magnesium Carbonate and some 50,000 tpa of Basic Monolithic Refractories. The company’s production facilities and main deposits are located in Chalkidiki, Northern Greece. The company is placing special emphasis on research and development of high added value products for a number of industries. Besides Greece, the company operates magnesia mines and production facilities in Turkey and participates in the leading magnesia producer of Spain.

Michael Tsoukatos
Development Director
GRECIAN MAGNESITE S.A
.