Feldspars in Turkey

By IM Staff
Published: Monday, 30 November 2015

Having recently overtaken Italy as the world’s largest producer of feldspar, Turkey dominates global supply of the ceramic and glass mineral and is expected to remain on top as global demand recovers, Aykut Karaca, IM Correspondent, finds.

Feldspars are important industrial minerals mined for their aluminium oxide (Al2O3), sodium oxide (Na2O) and potassium oxide (K2O) content. In loose terms, feldspar is a mineral group comprising aluminum silicates with varying amounts of potassium (K), sodium (Na) and calcium (Ca). More specifically, feldspars are tectosilicates (aluminosilicates), containing K, Na and Ca ions.

The general formula for feldspars is XY4O8, where X represents K, Na or Ca (or sometimes barium) and Y represents silicon (Si) or aluminum (Al). Feldspars are the most common rock-forming minerals, meaning that they are widespread in the Earth’s crust, making up approximately 60-65% of its content. However, despite its pervasive occurrence, exploitable deposits of feldspar are far less common. The mineral needs to occur in a large enough localised concentration and be of sufficient purity and quality to be classified as economically minable.

Feldspars are typically classified into two sub-groups: alkali feldspars (or K-feldspars) and plagioclase feldspars. Broadly speaking, alkali feldspars are the feldspars that lie between orthoclase (KAlSi3O8) and albite (NaAlSi3O8). That means feldspars with varying amounts of K and Na in solid solution belong to this category.  Some examples from this category are orthoclase, sanidine, microcline and anorthoclase (see diagram). 

Similarly, plagioclase feldspars are feldspars composed between anorthite (CaAl2Si2O8) and albite (NaAlSi3O8). This puts feldspars with differing quantities of Na and Ca in solid solution in this bracket, such as albite, oligioclase, andesine, labradorite, bytownite and anorthite.  

feldspar 

Glass and ceramics

 Albite, or Na-feldspar, is a common commercial feldspar. Albite is also the most common feldspar mined in Turkey.

Feldspars are exploited for their alkali or alumina contents. They are one of the main raw materials in the glass and ceramic industries, which are the largest and second largest end markets, respectively, for the mineral group. As each industry uses feldspars for a different purpose they have varying specific requirements for the properties of feldspar. In general, commercial feldspars must have low iron (Fe2O3) and refractory minerals (rutile, titanite, mica and Ti-minerals) content. 

In the glass making process, the three main ingredients required are glass formers, fluxes and stabilisers. Glass formers, as the name implies, are the materials that make up the glass, such as quartz sand. Fluxes are additives that contain alkali oxides, which help to reduce the melting temperature of the batch. Stabilisers are the components that give glass chemical and physical resistance. Feldspars are used both as a source of flux and as a stabiliser. The alkaline oxide content of feldspars, namely the amount of K2O and Na2O contained, acts as flux, encouraging the fusing of the glass formers and helping with mixing by reducing the viscosity of the system. The Al and calcium oxide (CaO) content of feldspars acts as a stabiliser, increasing hardness and resistance to external physical and chemical effects.

In the ceramics industry, feldspars are used as fluxes to decrease the melting temperature and promote the formation of the molten glassy fluid body. As with glass, it is the alkali content of the feldspars (K and Na) that acts as flux in this process. Feldspars also control the degree of vitrification of the ceramic body during fluxing. The amount of feldspars added as flux depends on the degree of vitrification desired and the type of final product. For example, for electro-porcelain, K-feldspar is preferred and added to form 20-28% of the batch mass.   

Thanks largely to its abundance of naturally occurring minerals, Turkey has a long and rich history of ceramic production. The region of Turkish Anatolia has one of the oldest cultures of low-fired earthenware, tiles and ceramics, the roots of which can be traced as far back as Uyghurs in the eighth century. Today, ceramics from Turkey are still highly regarded for their quality, durability, colour and design.

Feldspar in Turkey

Turkey is currently the largest producer of feldspar in the world, having overtaken Italy after years of competition. According to US Geological Survey (USGS) data, Turkey produced 5m tonnes feldspars in 2014, representing approximately 23% of total world production. Italy is close behind, with 4.7m tonnes feldspar mined last year. 

The main feldspar minerals mined in Turkey are albite and K-feldspar. The majority of the country’s feldspar deposits occur in western Turkey in the aplites and pegmatites of the Menderes massif. Aplite is a rock that forms dikes or veins with quartz and feldspar as the principal minerals. Pegmatites are intrusive magmatic rocks with large coarse crystals of minerals of irregular graininess.  

Other feldspar producers in Turkey*

Company

Location

Production (tpa)

Export (tpa)

Mineral

Camis Madencilik (Sisecam)

Milas/Yatagan

500,000

-

Na-Feldspar

KaleMaden

Cine/Milas

400,000

-

Na-Feldspar

MinMad Madencilik

Karpuzlu

350,000

200,000

Feldspar

Gurbuz Madencilik

Cine/Milas

-

-

Feldspar

Zafer Madencilik

Canakkale

-

-

Feldspar

Karoz Madencilik

Bilecik

-

-

Feldspar

B&S Yatırım

Milas/Yatagan

-

-

Na-Feldspar

Yıldızlar 3S Holding

Afyon

-

-

Feldspar

*Production/export data unavailable for some companies

Companies, production and export

Around 90% of Turkey’s feldspar production is exported. According to the eighth and tenth five-year development plan reports by the Turkish Ministry of Development, published
in 2000 and 2015, Turkey has established itself as an important supplier of ceramics and ceramic raw materials to both European and global markets. 

Current domestic production of albite is judged to be sufficient to supply Turkey’s own glass and ceramic industries, however the ministry’s reports noted that the country has limited resources and production of K-feldspar to satisfy its internal demand, forcing Turkey to import the material over the last decade and a half.

The largest Na-feldspar deposits in Turkey are located in the Aydin-Cine and Mugla-Milas areas. K-feldspar deposits are found in Kutahya-Simav, Manisa-Demirci, Gordes, Bilecik-Sogut and Akkoy, meanwhile.

Some of the companies that produce feldspars in Turkey are detailed below, with other producers listed in the table below.

Cine Akmaden Madencilik AS

The firm was established as a collective company with five owners in 1978. It is now an incorporated company with nine owners. Cine Akmaden has 17 operational and 10 pre-operational mines and 11 exploration licences. Six of those licences are under the name of Cine Akmaden whereas the rest belong to Cine Akmaden’s sister mining company, Alinda Madencilik San. ve Tic. AS. According company data, the business has three active quarries with over 100m tonnes reserves of albite (at Aydın-Karpuzlu and the Usak -Aktopraklı/Kayalı areas), and 1.7m tonnes reserves of K-feldspar (in Mugla-Kavaklıdere). The company produced more than 1.2m tonnes feldspars in 2006 and around 830,000 tonnes of this was exported in the same year. Akmaden also opened a subsidiary in Italy in 2003 in order to be closer to its existing customers in the country and to reach smaller potential clients. 

Kaltun Madencilik Sanayi ve Ticaret AS

Kaltun Madencilik Sanayi ve Ticaret AS was established in 1962 and covers 16 businesses, which together make up the Kaltun Group. Ten of them are involved in the production and trade of industrial raw materials, while the others focus on agriculture, shipping and energy.  

Through its mining arm, the company is one the world’s largest miners of feldspar. It produces around 2m tpa of Turkey’s total feldspar output, which in 2014 stood at 5m tonnes, according to the USGS. Kaltun Mining conducts open pit mining at locations in the Cine-Milas-Yatagan region. As well as its Turkish business, Kaltun has four foreign companies based in Italy, Spain, Egypt (where it has further feldspar deposits) and the Netherlands.

feldspar2 Toprak Holding – Toprak Madencilik

Toprak Holding is a large conglomerate of companies in Turkey working in several different industries including paper, tiles, ceramics, construction materials, medicine, tourism, energy, iron casting and mining. Toprak Madencilik is its mining arm and was established in 1984. The company produces enough feldspar to supply its own factories and sells the remainder on the open market. Toprak Madencilik has licences in eight provinces in Turkey and more than 20 quarries producing over 1m tonnes raw materials, including Na-feldspar, K-feldspar, quartz, clays, calcite, dolomite and magnesite. According to the Ministry of Development, in 2000, Toprak Madencilik produced around 250,000 tpa Na-feldspar from its quarry in Mugla-Milas.

Matel AS

As a part of the Elginkan Holding group, Matel was established in 1980. Initially, it produced raw materials from its quarries in Bilecik, Balıkesir and Mugla, but after a revision of Turkey’s mining law in 1985, the company started exploring for further mineral deposits and identified large resources. It has a clay refinery in Bilecik, opened in 1989; a crushing facility in Mugla-Milas which it established in 1993 and now has a capacity of 250,000 tpa; a laboratory, opened in 1995, for chemical, physical and mineralogical analyses of ceramic minerals; and a micron size pulverisation plant for feldspars and quartz which was opened in Bilecik in 2000. 

Today, Matel has 16 mining licences in eight provinces for various industrial raw materials including Na-feldspar, K-feldspar and syenite (a rock containing feldspars and quartz). According to the Ministry of Development, in 2000, Matel had around 180,000 tpa Na-feldspar production from its quarry in Mugla-Milas and around 100,000 tpa syenite production from its mine in Bursa-Orhaneli. According to the company, 25% of its production is exported and it controls 5m tonnes feldspar reserves and 20m tonnes syenite reserves.

Eczacibasi Esan

Part of the Eczacibasi Holding conglomerate, Esan was established in 1978. In addition to producing minerals such as feldspar, clay and quartz, Esan also operates in the chemicals, insulation materials and ceramic ovens sectors. In 2014, Esan had 24 active quarries and six beneficiation plants in Bozuyuk, Bandırma, Cine and Milas. Esan has a capacity to produce 650,000 tpa floated and 50,000 tpa raw feldspar.

The company also established a branch in Italy (Esan Italia Minerals) in order to serve its locally-based customers.

Imerys Seramik Hammaddeleri San ve Tic AS

France-based industrial minerals giant Imerys has been in active in the Turkish feldspar market since 2008 and has been producing and selling feldspar from its Milas operation since 2010.

Outlook for Turkish feldspar

According to a 2010 report by the Chamber of Mining Engineers of Turkey, global feldspar production in the last 25 years has been steadily increasing at a rate of 2-3% per annum. 

USGS data suggests that the steady recovery in the worldwide ceramics industry will continue over the next five years. Demand for feldspars is therefore likely to increase, with key market drivers being ceramic tiles and glass used in the construction industries of China, India, Brazil and Indonesia.  

Turkey is likely to remain dominant in the global feldspar market for the foreseeable future. Resources, particularly of Na-feldspars, are thought to be sufficient to support Turkey retaining the number one supply position. Although it is hard to quantify the country’s total reserves, as there might be other geological sources of feldspars, such as from gneisses and feldspar sands, some sources indicate that Turkey has 400m tonnes Na-feldspars, whereas others suggest it has more like 240m tonnes.