As a result of fast-expanding construction activities in Estonia in recent years, the consumption of construction materials has increased while the security of supply of construction minerals has decreased.
Overview of Estonian construction minerals
Estonian bedrock construction minerals mainly formed during the early Paleozoic era. Gravel deposits and most sand and clay deposits are located in the Quaternary sediments which cover the bedrock.
Only one deposit has been registered as a mineral resource from among the deeper crystalline basement rocks – Maardu granite deposit in Harju County.
The highest-quality construction limestone in Estonia is the Väo formation limestone, the superficial deposit of which runs west to east in Northern Estonia. The most important limestone deposits of Väo formation are Harku, Väo, Maardu, Jägala and Kunda.
In Estonia, sand and gravel are widely used construction minerals and their deposits are relatively evenly spread across Estonia. However, the quality indicators of both sand and gravel may differ significantly even within one deposit. The most important sand and gravel deposits are Tallinna-Saku, Kuusalu, Huntaugu, Pannjärve, Kose-Risti, Partsi and others.
In recent years, clay has been extracted to only a very limited extent in Estonia; the main types include cement and ceramic clay. The most important clay deposits are Aseri and Kunda.
The economically efficient and sustainable use of mineral resources has been defined by the Earth's Crust Act.
The requirements for both construction minerals and other mineral resources have been established by Regulation No. 52 of the Minister of the Environment on the basis of the Earth's Crust Act.
Construction minerals extracted and used in Estonia
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Carbonate rocks are classified as limestone or dolostone depending on their content of magnesium.
Limestone is composed of Ordovician and Silurian carbonate mud and less frequently of Devonian carbonate mud (CaCO₃ content in the rock >50%).
Dolostone is formed as a result of large volumes of additional magnesium in the rock leading to dolomitisation (CaMg(CO₃)₂ content in the rock >50%).
- Sand and gravel are genetically closely related clastic sediments primarily formed during the Quaternary period and, to a lesser extent, during the Devonian period.
Sand is a fine-grained clastic sediment composed of finely divided quartz and feldspar mineral particles.
Gravel is a coarse‐grained clastic sediment composed of igneous, metamorphic and sedimentary rock pebbles and cobblestones. - Clay is the finest-grained clastic sediment formed during the Quaternary and Cambrian periods, primarily containing clay minerals (may also contain aleurite and fine sand).
EGT reports on construction minerals in the Geological Archive
Contact
Janne Tamm
Senior Geologist
