Since antiquity, Cyprus was well known for its rich copper ores and for three thousand years was the biggest centre for mining and exporting of copper. Furthermore, since the Paleolithic era, stones were used as primary building material, initially in their natural form (rubble stone), i.e. as they are found in nature and later on, as cut and carved stones (ashlar stone). Calcarenite was the predominant rock type that was used to make the first stone tools and built the archaeological sites. Gradually other mineral resources were discovered and used since ancient times such as gypsum for mortar and clay for production of terracotta and clay pots. These mineral resources constitute essential raw materials to industry and in recent time, their exploitation continues and enhances with further uses.
Metallic Minerals
During the last century there has been extensive exploitation of copper deposits and production of copper concentrates. In 1996, the environmentally friendly method of hydrometallurgy was applied for the first time in Cyprus and in Europe, in the Skouriotissa mine. With this method, the ore is pilled in heaps and sprinkled with acidic solution rich in chemolithotrophic (rock-eating) bacteria. The derived solution is then treated in a solvent extraction plant where the electrolysis of the solution follows, leading in the production of metallic copper with content 99.999% Cu.
Geological investigations, during the 1920s, identified a chromite deposit of economic importance and in 1935 the exploitation of chromite ore began in three underground mines (Hadjipavlou, Kokkinorotsos and Kannoures) and it was exported for various industrial uses. During the 1980s, due to international price fall, the exploitation of chromite ceased to be economically profitable and the mines were closed. The remaining chromite reserves are estimated at about 300.000 tons.
Asbestos
Cyprus was known for its asbestos since the Classical and Roman time that it was used for making textiles for incineration, shoes, and fireproof materials. The main deposits of chrysotile asbestos occur in zones of intense serpentinisation of harzburgite in the eastern part of the Troodos ophiolite, over an area of about 20km2 near the village of Amiantos. Asbestos is found in veins, the thickness of which reaches 30mm. The average grade of the deposit was approximately 0.8-1 %. The exploitation of asbestos began in 1904. The operation of asbestos mine was profitable until 1981. After 1981, the increased use of synthetic substitutes of asbestos caused in to the drastic reduction of the asbestos demand, and as a result, the mine faced economic problems, which combined with environmental problems led to its final closure in 1992. About 130 million tons of rock was mined to produce about one million tons of fibres. The asbestos mine is currently under environmental rehabilitation and it is an international study-case for the restoration of an asbestos mine.
Industrial Minerals
Aggregates are basic raw materials for the building industry and road construction. They can be any of several hard, inert materials used for mixing cement or bitumen to form concrete, mortar or plaster or used alone as in graded fill. Aggregates are characterized as coarse (gravel) or fine (sand) depending on their particle size and natural or crushed depending on their source. The rocks used as raw materials for the production of aggregates are diabase, reef limestone and calcarenite. They are extracted from open pits and undergo crushing, screening and whenever necessary washing. There are 22 quarries operating, ten in diabase, ten in reef limestone and two in calcarenite.
Gypsum is a soft evaporate mineral, which has been used as a construction material for centuries. Gypsum deposits are extensive in the island, reaching the thickness of 150m. It appears as laminated microcrystalline layers, selenite crystals and alabaster. Today, gypsum is produced in the form of plaster and filler. Gypsum is also used for the production of cement, along with chalk and marl. The laminated gypsum is used for internal floor tiles in buildings with traditional architecture.
Bentonite has a very high plasticity, good swelling properties and variable colour from greenish grey/yellowish brown to khaki or pinkish. It is an industrial mineral with a variety of uses, due to its ability to swell with absorption of water and shrink with the expulsion of water. The amount of water it can absorb reaches five times its weight and is associated with an increase of its volume of up to 15 times. This characteristic capacity can be repeated many times. Bentonite is excavated periodically from shallow quarries and transported to factories where it is laid down to dry and is blended before processing. Most of the bentonitic clays from Cyprus are exported for use as pet litter. A sodium activation process has been developed to improve the properties of the natural bentonite. Bentonite outcrops widely around Troodos, covering an area of about 80km2. The total resource is estimated around 2 billion tonnes.
Clay is a basic raw material for the production of bricks, tiles and pottery as well as one of the basic raw materials of the cement industry. It is a fine-grained natural sediment or soft rock composed of clay-sized colloidal particles and characterized by high plasticity. The typical Cyprus clay is mainly composed of montmorillonite and on a later degree of clay minerals of the illite and kaolin groups. In addition, it includes very fine fragments of quartz, decomposed feldspars, carbonates, ferruginous mater and other impurities. In Cyprus, clays that are of the montmorillonite and smectite groups are extracted in various locations from the sedimentary deposits of the Nicosia Formation and from weathered, reworked and redeposited igneous rocks of the Ophiolite (red clay).
In Cyprus, building stone was for centuries the main construction material. The type of stone was diachronically related to the rocks of each area. In the Troodos Mountains rocks from the ophiolite, such as gabbro, diabase, harzburgite were used. In other areas chalk, limestone and calcarenite were used as building stones. Calcarenite was extensively used in Cyprus for the construction of fortifications such as the Venetian Walls of Nicosia, castles, as well as public buildings, churches, and mansions. Even though all of the above types of natural building stone are still produced and used today, their primary use has been shifted from building to decorative (dimension stones). The building stone products are manufactured to be used for cladding as well as internal and external floor paving. At present, calcarenite of the Pakhna Formation is used as decorative stone. Also as building and decorative stone are used the massive and silicified chalks and laminated gypsum.
Cyprus was also known in the antiquity for its natural pigments such as umber (dark, iron-bearing sediment), ochre (iron oxides and hydroxides) and terra verde (celadonite). The exploitation of these materials is still ongoing through sporadic quarrying, processing and exporting.
Chalk, marl and gypsum are the main raw materials used for the production of cement and there are mineral resources that are found in abundance in Cyprus.