Колмаківське родовище

The productive layer of the Kolmakivske deposit consists of coarse-, medium-, and fine-grained quartz sands belonging to the Kyiv (or, according to an alternative interpretation, Buchak) Formation of the Paleogene, or the Upper-Middle Sarmatian Substage of the Neogene. The thickness of the productive sequence ranges from 2.8 to 11.8 m, with an average of 6.8 m. Overburden thickness varies from 3.2 to 12.2 m, averaging 10.0 m. Hydrogeological conditions of the deposit are favorable: the groundwater table lies below the productive layer, allowing for open-pit mining.

The sands do not fully comply with the requirements of GOST 8736-58 regarding particle size distribution, as individual samples contain an elevated amount of particles passing through a 0.15 mm sieve. However, technological testing has established that provided the content of grains smaller than 0.15 mm does not exceed 13.0–13.6% and the total content of clay and silt particles is no more than 6.7%, the sands are suitable for use as fine aggregate in concrete. Direct performance testing in concrete mix confirmed their full suitability for the production of concrete products.