General information and occurrence
The basic raw materials used for a building ceramics production are various clayey rocks which mixed with water form a plastic mass easy to form and sands so-called “weaken sands” which are added to a clayey raw material to improve the properties of the ceramic mass. The formed and burnt products must be of the appropriate physical and technical features defined by the official standards. Clayey and non-clayey (weaken) raw materials often occur together - in one deposit, in the form of beds or interbeddings, or as the independent accumulations.
The main building ceramic products are: ceramic bricks and breezeblocks, slates, clinker bricks, fittings, ceramic pavements. The raw material from some deposits is being used also for the production of enamel ceramic tiles, stoneware products, ceramic accessories and others.
The raw materials for the building ceramics production owe their yielding features and their ability to be formed to the clayey minerals content. Their content in different rocks varies. In loesses the clayey minerals content is low (couple of %), but in clays it can be up to 100%. Usually in the typical raw materials the content is between 40% and 60%. Other components are mainly the quartzitic sand and dust, feldspars, calcite and dolomite in calcareous raw materials, iron minerals, mica minerals and organic matter. Clayey rocks built of only one mineral occur very seldom, they mostly have several clayey minerals in their composition: kaolin, illite, montmorillonite and chlorites, occurring together in changeable proportions.
Building ceramics raw materials occur commonly in the whole country. They vary in terms of their origin and age. Nowadays, the most important raw materials are these of the Quaternary, Neogene, Jurassic and Triassic age. The raw materials of the Quaternary age include mainly stagnant lake sediments such as muds and clays occurring mainly in northern and central Poland. There are also loesses, glacial loams, alluvial loams and loams of weathering covers and sands used. Among older minerals the most important are the Neogene clays of the so-called Poznań Series from south-western and central Poland and those of the Krakowiec clays from the area of the Carpathian Foredeep in south-eastern Poland. The Jurassic and Triassic deposits are situated at the margin of the Holy Cross Mts., in the Czestochowa region and in the Opole region. The building ceramics raw materials deposits in Poland are presented on the map.
According to the Regulation of the Minister of the Environment of the 1st of July 2015 regarding the geological documentation of a mineral raw material deposit, excluding a hydrocarbons field (number of Polish act: Dz. U. 2015, poz. 987) the limit values of the parameters that define the building ceramics raw materials deposit and its borders (Appendix 8 – table 42) are: - the maximum documentation depth – to the depth of a possible exploitation; - the minimum thickness of the deposit – 2 m; - the maximum overburden/thickness ratio – 0.5; the maximum content of grains bigger than 2 mm – 1%; - the maximum content of a ceramic marl in grains diameter bigger than 0.5 mm – 0.4%; - the shrinkage in drying minimum 6%.
Resources and output
The table given below shows reserves and the state of development and exploration of clay raw material for the building ceramics industry.
The anticipated economic resources of the building ceramics raw materials amounted to 2,038.635 million m3 (about 4,077.270 million tonnes) as of the end of 2019. They decreased by 5.617 million m3 (about 11.234 million tonnes – that is by 0.3%) in comparison with the previous year.
There were not any new deposits of the building ceramics raw materials documented in 2019, however there were 22 new documentations with recalculated resources approved, including: 14 supplements updating the deposits boarders and resources, and 8 supplements with resources settlements.
The new documentations with updated boarders and resources, were elaborated for the following deposits: Ruszowice II (-0.006 million m3) in Dolnośląskie Voivodeship, Słodków – Stróża (0.020 million m3), Słodków IV (0.065 million m3) and Suchynia II (0) in Lubelskie Voviodeship, Łukowa I (-0.015 million m3) in Małopolskie Voivodeship, Czerwone Osiedle (1.395 million m3) and Konradów Głuchołaski (-0.107 million m3) in Opolskie Voviodeship, Zalesie Gorzyckie – Dul 8 (0), Zalesie Gorzyckie – Dul VII (0), Zalesie Gorzyckie – Dul III (0) in Podkarpackie Vovivodeship, Sierakowice (-1.545 million m3) in Śląskie Voivodeship, Odonów (-1.118 million m3) in Świętokrzyskie Voivodeship and Bukowo (Wschód) (-0.010 million m3) and Złocieniec (-0.063 million m3) in Zachodniopomorskie Voivodeship.
The supplements with the resources settlement, where the basis for crossing out 9 deposits from “The balance…”: Dąbrowa II (-0.042 million m3) in Łódzkie Voivodeship, Bonarka-Łagiewniki (-2.045 million m3) and Krościenko (-0.092 million m3) in Małopolskie Voivodeship, Guzowatka III/1 (-0.030 million m3), Babiec Piaseczny II (-0.000 million m3) and Mokre – dz. Nr 373/2 (-0.041 million m3) in Mazowieckie Voivodeship, Gorzyce – Cetnarski II (-0.004 mln m3) in Podkarpackie Voivodeship, Świba (-0.020 million m3) and Słupia (-0.033 million m3) in Wielkopolskie Voviodeship. The total resources drop amounted to 2,265 million m3. The significant resources volume of Bonarka-Łagiewniki were crossed out from “The balance…” due to “the raw material quality – the high sulfate salts content, the deteriorating quality of products as the result of the mine location in the center of Cracow town”. Babiec Piaseczny II deposit was crossed out from “The balance…” due to the resources depletion. In other cases, there were the geological reasons: the bad raw material quality and difficult geological-mining conditions, and economic reasons: the resignation of the exploitation process (probably due to the unprofitable of the ceramic articles production) and the plans to the land development for other purposes.
Out of 1,133 documented deposits of the building ceramics raw materials, exploited deposits account for 12.7% (including: 7.5% deposits exploited continuously and 5.2% deposits exploited temporarily), non-exploited deposits account for 26.7% (including: 20.1% deposits covered by a detailed exploration and 6.6% deposits covered by a preliminary exploration) and abandoned deposits account for 60.6%.The number of abandoned deposits – reported in the domestic records – has been increasing systematically for many years.
Out of the total amount of the anticipated economic resources, the resources within exploited deposits account for 12.4% (including: 10.6% deposits exploited continuously and 1.6% deposits exploited temporarily), the resources within non-exploited deposits account for 71.2% (including: 11.4% in the deposits covered by a detailed exploration and 59.8% in the deposits covered by a preliminary exploration) and the resources within abandoned deposits account for 16.4%.
Resources documented in A+B and C1 categories (the detailed exploration) account for 34.5% of total anticipated economic resources. The remaining part of resources is documented in C2 or D categories (the preliminary exploration). More than a half of resources covered by the preliminary exploration (59.7%) are resources documented within the overburden of non-exploited brown coal deposit Legnica-pole Wschodnie (727.65 million m3 of clays documented in C2 category).
The economic resources were documented for 74 deposits and amounted to 154.226 million m3 (about 308.452 million tonnes) that accounts for 60.2% of the anticipated economic resources of these deposits. The economic resources in 2019 increased by 17.946 million m3 (13.2%) in comparison with the previous year. There were the economic resources updated for Gozdnica deposit (the resources drop was recorded in 2018), Oleśnica 1 deposit (+21.543 million m3), Wola Rzędzińska (-6.047 million m3 were reclassified to the sub-economic resources). There were the economic resources established for Kębłowo Nowowiejskie II deposit (+4.744 million m3). The resources of Hadykówka deposit were crossed out from “The balance…” due to the abolition of the mining area (-1.508 million m3).
In 2019, the output of the building ceramics clays was equal 1.798 million m3 (about 3.596 million tonnes) and decreased in comparison with 2018 by 0.244 million m3 (12.0%). The exploitation was being carried out from 85 deposits.
Considering particular Voivodeships, the output was as follows (in a descending sequence): in Świętokrzyskie Voivodeship 0.357 million m3 (19.9% of the domestic output); in Śląskie Voivodeship 0.241 million m3 (13.4%); in Podkarpackie Voivodeship 0.211 million m3 (11.7%); in Małopolskie Voivodeship 0.157 million m3 (8.7%); in Dolnośląskie Voivodeship 0.143 million m3 (7.9%), in Mazowieckie Voivodeship 0.130 million m3 (7.2%); in Opolskie Voivodeship 0.117 million m3 (6.5%); in Pomorskie Voivodeship 0.104 million m3 (5.8%); in Wielkopolskie Voivodeship 0.075 million m3 (4.2%); in Lubuskie Voivodeship 0.064 million m3 (3.6%); in Zachodniopomorskie Voivodeship 0.064 million m3 (3.6%); in Lubelskie Voivodeship 0.060 million m3 (3.3%); in Łódzkie Voivodeship 0.032 million m3 (1.8%); in Podlaskie Voivodeship 0.031 million m3 (1.7%); in Warmińsko-Mazurskie Voivodeship 0.008 million m3 (0.4%); in Kujawsko-Pomorskie Voivodeship 0.004 million m3 (0.2%).
The figure given below shows changes in the domestic resources and production of the clay raw material for the building ceramics industry in Poland in the years 1989-2019.
In The balance of prospective mineral resources of Poland, the prognostic resources (category D1) of the building ceramics raw materials were assessed to be equal 1,328 billion m3 within 65 areas, moreover there were 267 prospective areas described (category D2 without the resources assessment)*. The majority of the prognostic resources is formed by the Neogene clays of the Poznań series (45.7% of the prognostic resources, from which 20% are the clays accompanying the brown coal deposits), the Miocene marine clays (33.3%), the stagnant clays (18.3%) and other (2.7%). The geographical distribution of the resources is uneven: in Dolnośląskie Voivodeship there is 43.1% of the resources located, in Podkarpackie Voivodeship 28.2%, in Podlaskie Voivodeship 9.2%, in Warmińsko-Mazurskie Voivodeship 5.1%, in Śląskie, Pomorskie, Świętokrzyskie and Małopolskie Voivodeships – from 2% to 3%, and in the remaining Voivodeships – 6.2% in total. Except for the determined areas, there are also other possibilities for the valuable clayey raw materials discovery.
Table 1. Building ceramics raw material - million m3