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Copper and gold
The mining history of Cyprus has connected the name Cyprus, with the name of copper (Cuprous). The production of copper in Cyprus began 3000 BC on a full scale. The ancient Cypriots were not only experienced miners but also skilful metallurgists. They discovered almost all copper ore bodies which have been exploited in modern years, and they were able to recover the rich part of the ore bodies by underground exploitation methods and produce high grade metal copper (copper talents) by metallurgical methods, of which their base is still used today. It is remarkable that the waste of the metallurgical treatment, known as ancient slug, has minimal residues of copper. Ancient slug may usually be found near various copper mines and is protected from the legislation as an ancient monument
In modern years, copper exploitation began around 1921 from the area of Skouriotissa and was continued intensely up to 1974. Underground and surface exploitation methods were used for ore recovery. The main underground methods which were used were the horizontal successive slices or levels followed by roof falling (top slicing, sub level caving) or fulfillment of the voids by stone filling or hydraulic filling using cement pulp containing tailings from the metallurgical treatment plants (cut and fill, crosscut). The main surface method was that of the closed benches, primarily because of the topography of the mining areas. The exploitation of copper sulfide minerals led simultaneously to the recovery of other sulfide minerals, mainly the iron pyrite. The metallurgical methods which were applied were mainly those of flotation of copper minerals (chalcopyrite, bornite, covellite, chalcosite and cuprite), iron pyrite and other sulfide minerals (sphalerite), if contained in the ore. The enriched copper ores (copper concentrates) had an average content of about 19% and were exported from Cyprus. Because certain copper minerals (malachite, azurite, chrysocolla and partly chalcosite and cuprite) are dissolved in water (leaching), the dissolved copper was cemented with scrap iron producing copper cement with a content of about 55-65%. In the latter years of the operation of the Xero treatment plant (closed in 1974), a pressure copper leaching in autoclaves was applied on the tailings of the plant. It was then followed by clarification of the copper solution and cementation with scrap iron, achieving a content of about 70% of copper in the copper cement product. The method of dump leaching using thin acidic solution – cementation with iron - production of copper cement was applied systematically from 1982 to 1993 on the low grade dumps of Skouriotissa copper mine. The only mining activity that existed in Cyprus from 1996 to 2019, was the copper mine of Skouriotissa which produced copper metal cathodes (99.999%) applying the Leaching – Solvent Extraction - Electowinning method (Leaching - SX - EW).
The main floatation treatment plants were in the Nicosia district at Xero (CMC) and Mitsero (HMC), in the Larnaca district at Vasilico (HMC) and in Paphos district at Limni (CSCC).
On the page below you may find the main copper and iron pyrite mines which operated in Cyprus since 1921 as well as the total exports of the products of these mines since 1931. Information for the current copper prices but also for other metal prices may be found in the website of «London Metal Exchange».
In certain mines but also from other smaller mining excavations, gold and silver were occasionally produced. The gold and silver product was in the form of inclusions or free grains of metal in the copper and iron pyrite flotation consecrates. The product could also be gold and silver consecrate produced from the ores which were found at the upper surface of the mines (iron caps) and were mainly leached lava. Also, cyanide leaching was applied to certain forms of these ores of gold and silver followed by zinc dust precipitation and the production of gold and silver precipitants. From mid 2017 until 2020, had operated at Skouriotissa Mine, a gold-silver alloy production plant applying cyanide heap leaching - absorption / desorption by activated carbon - electrowinning. The occasional exports of these gold and silver products are shown in the table below in kilos of content metal.
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