17/ Rožmitál quarry: Mining and raw material

Area: 41 ha (quarrying area), 72 ha (protected deposit area)
Mined rock: basalt-andesite (also known as melaphyre) – volcanic rock with low to medium silica oxide content
Volume of mining: an average of 100 000 tonnes per year

 

The Rožmitál quarry has been in operation since 1965. Its owner and operator is the Agricultural Cooperative Šonov u Broumova. It produces quarry stone, gravel, coarse crushed, and graded aggregates in fractions from 4 to 125 mm. These are then used for construction purposes and as gritting material.

 

Between 1965 and 2003, mining took place on Homole Hill and is currently continuing in the northern part of the quarry area, where the stone is mined in five ‘etages’ (582, 568, 545, 525, and 505 m above sea level). The deposit is quarried using the level mining method, with the rock being disconnected by means of blasting. The breaking of large pieces of rock is carried out using a hydraulic hammer MB 750 Dust mounted on a Liebherr A312 wheel excavator. The broken stone is loaded by DH-631, DH 28.1 and Liebherr R 964 HD excavators, while T-815-S1 trucks are used to transport the stone to a crusher. The process line consists of a hopper with a feeder, a despoiler (a machine separating soil from stone), a V7-2N crusher (first crushing stage), and a DKT 900 cone crusher (second crushing stage). The crushed stone is sorted on a four-sieve vibrating classifier. The sorted aggregate is stored in bins and in an earth dump. Various fractions are produced in the gravel pit, which differ in the particle size of the stone gravel.