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. 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 inter-beddings, or as independent accumulations.
The assortment of building ceramic products contains mainly: 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 %), whereas 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 sand and quartzitic 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 usually 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 deposits 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 maritime Miocene clays occurring in south-eastern Poland in the area of the Carpathian Foredeep. 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 boundaries (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 2,030.702 million m3 (about 4,061.404 million tonnes) as of the end of 2021. They decreased by 2.878 million m3 (about 5.756 million tonnes – that is by 0.1%) in comparison with the previous year.
There was 1 new deposit of the building ceramics raw materials documented in 2021: the Gorzyce – Cetnarski IV deposit (0.009 million m3) located in Podkarpackie Voivodeship.
For 18 deposits there were new documentations with recalculated resources approved (supplements for documentations), from which: in 12 cases there were decisions of crossing out the deposits from “The balance…” made. The new documentations (supplements), updating the boundaries and resources, were prepared for the following deposits: Małopole II K (-0.075 million m3) in Mazowieckie Voivodeship, Górki – Głowacki II (-0.001 million m3) in Podkarpackie Voivodeship, Sucumin (+0.008 million m3) and Niezabyszewo (-0.019 million m3) in Pomorskie Voivodeship, Ogrodzieniec (-0.005 million m3) in Śląskie Voivodeship, Witaszyce (-0.243 million m3) in Wielkopolskie Voivodeship. The total resources drop resulting from the above mentioned documentations (supplements) was equal 0.335 million m3. There were following deposits crossed out from “The balance…”: Lublin-Przejrzysta (0.101 million m3) in Lubelskie Voivodeship, Nowy Sącz – Załubińcze I (0.109 million m3) in Małopolskie Voviodeship, Słupno-Górki (0.003 million m3) and Guzowatka 4 (0.163 million m3) in Mazowieckie Voivodeship, Niwnica (0.129 million m3) in Opolskie Voivodeship, Chwałowice – Bałdos I (0.000 million m3), Pniów – Bera VIII (0.000 million m3), Gorzyce – Cetnarski III (0.002 million m3) in Podkarpackie Voivodeship, Gnaszyn Górny (0.049 million m3) and Zofia (0.014 million m3) in Śląskie Voivodeship, Wyszyna Machorowska III (0.022 million m3) in Świętokrzyskie Voivodeship, Oracze (0.030 million m3) in Warmińsko-Mazurskie Voivodeship. The resources of the Rozpędziny deposit in Pomorskie Voivodeship (0.064 million m3; that is 0.109 million tonnes of weaken sands) were reclassified to the group of “sand and gravel”. The total resources drop resulting from crossing out the above mentioned deposits is equal 0.686 million m3.
Out of the total 1,123 documented deposits of the building ceramics raw materials, exploited deposits (114) account for 10.2% (including: 6.3% deposits exploited continuously (71) and 3.8% deposits exploited temporarily - 43), non-exploited deposits (301) account for 26.8% (including: 20.2% deposits covered by a detailed exploration (227) and 6.6% deposits covered by a preliminary exploration - 74) and abandoned deposits (708) account for 63.0%.
Similarly, out of the total volume of the anticipated economic resources (2,030.70 million m3): the resources within exploited deposits (245.27 million m3) account for 12.1% (including: 10.2% deposits exploited continuously (207.57 million m3) and 1.9% deposits exploited temporarily – 37.70 million m3), the resources within non-exploited deposits (1,443.77 million m3) account for 71.1% (including: 11.3% in the deposits covered by a detailed exploration (230.23 million m3) and 59.8% in the deposits covered by a preliminary exploration – 1,213.54 million m3) and the resources within abandoned deposits (341.66 million m3) account for 16.8%.
The 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 (60%) 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 are documented for 72 deposits and amount to 140.731 million m3 in total (about 281.462 million tonnes) that accounts for 57.0% of the anticipated economic resources of these deposits. The economic resources in 2021 decreased by 11.065 million m3 (7.3%) in comparison with the previous year. The resources increases amounted to 0.021 million m3. The resources drops were equal 11.086 million m3, including: the corrections of economic resources for the following deposits: Kunice I – wschód (-0.884 million m3 of weaken sands) in Dolnośląskie Voivodeship and Chełsty (-5.627 million m3 – the data updating) in Łódzkie Voivodeship; due to the concession extinction and removal of the mining areas, there were economic resources crossed out for the following deposits: Chwalimierz II (-1.620 million m3) and Leszczyna Kłodzka (-0.231 million m3) in Dolnośląskie Voivodeship, Guzowatka 4 (-0.155 million m3) in Mazowieckie Voivodeship, Branice (-0.150 million m3) in Opolskie Voivodeship, Podborze (-0.196 million m3) in Podkarpackie Voivodeship and Sągnity (-0.275 million m3) in Warmińsko-Mazurskie Voivodeship; the remaining resources drops (-1.948 million m3).
In 2021, the output of the building ceramics clays was equal 1.714 million m3 (about 3.428 million tonnes) and increased in comparison with 2020 by 0.149 million m3 (9.5%). The exploitation was being carried out from 72 deposits (including the Wyszyna Machorowska III deposit from which the exploitation ended in 2021 and the deposit was crossed out from “The balance…”). Considering particular Voivodeships, the output was as follows (in a descending sequence): in Świętokrzyskie Voivodeship 0.280 million m3 (16.4% of the domestic output); in Podkarpackie Voivodeship 0.218 million m3 (12.7%); in Dolnośląskie Voivodeship 0.192 million m3 (11.2%); in Śląskie Voivodeship 0.152 million m3 (8.9%); in Małopolskie Voivodeship 0.149 million m3 (8.7%), in Pomorskie Voivodeship 0.142 million m3 (8.3%); in Opolskie Voivodeship 0.137 million m3 (8.0%); in Mazowieckie Voivodeship 0.117 million m3 (6.8%); in Lubuskie Voivodeship 0.096 million m3 (5.6%); in Wielkopolskie Voivodeship 0.078 million m3 (4.6%); in Lubelskie Voivodeship 0.062 million m3 (3.6%); in Łódzkie Voivodeship 0.058 million m3 (3.4%); in Kujawsko-Pomorskie Voivodeship 0.018 million m3 (1.0%); in Podlaskie Voivodeship 0.014 million m3 (0.8%); in Warmińsko-Mazurskie Voivodeship 0.001 million m3 (0.1%); in Zachodniopomorskie Voivodeship 0.000 million m3 (0.0%).
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 1989-2021.
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 given (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.