Zagrad

Red bauxite ore deposit called ‘Zagrad’ is located 15 km east of Nikšić, in the region called Nikšićka Župa.

Geomorphologically, this part of the terrain belongs to south-west slopes of Maganik mountain, i.e. to its spurs.

The very deposit is located in karst valley of Oblatno village, with its upper part stretching along karst valley of Zagrad village, with altitude ranging from 860 and 970 meters. On the southern side of the deposit, a hill called Klobuk is located (1.045 m), whereas its northern side is surrounded by Zmijinice (1147 m) and Jaroša (1141m).

Red bauxite deposit ‘Zagrad’ is connected to Nikšić by a wide tarmac road.

Geological structure

Geological structure of wider Zagrad area consists of carbonate sediments of Triassic, Jurassic and Cretaceous, and quarter sediments. Triassic is represented by massive limestones with megalodon. Regression happened during Upper Triassic. During dry – land phase, that lasted until Teton, red Jurassic bauxite was created. Transgression upper Jurassic sediments are represented by layered limestones with marly and clayey scuds in lower part of the pillar. Jurassic – Cretaceous complex is built of limestones, dolomite and dolomitic limestone. Moraine materials, built of sand, boulder, big – size pebbles and limestone blocks of larger size, take much of the area, having the width up to 100 m. In tectonic terms, Zagrad area is characterized by ruptures – of gravitational type.

Bauxite quality

The mineral composition of bauxite is made of: boehmite (65,57%), kaolinite (10, 36%), hematite (19,13%), calcite (2, 93%) and anatase (2,88%). This research showed that bauxite in Zagrad deposit belong to I type of mono-hydrant red bauxite of boehmite type.

According to the information obtained by earlier research, bauxite in Zagrad deposit contains numerous micro elements with composition in ppm: Pb- 36, Ga-30, V-180, Cu-25, Y-50, Zn-600, Zr-330, Ni-120, Co-22, Cs-42, Cr-450, La-100, Ba-14, Sr-37, Li-12, Rb-10, U-6 and Th-58.

Volume and specific mass of bauxite in Zagrad deposit has been analysed on 20 samples. Arithmetic mean of volume mass of bauxite is 2,65 t/ m3.

Mineral and qualitative characteristics of Zagrad deposit enable implementation of Bayer’s process to produce aluminum.  Raw material may be used even for production of electro corundum and other abrasive materials.

Bauxite reserves

Last calculation of red bauxite reserves in Zagrad deposit has been carried out within the Study on classification, categorization and calculation of red bauxite reserves in Nikšićka Župa deposits: Zagrad, Biočki stan, Đurakov do, Štitovo II and Borovnik, status on 31 December 2006, using a method of parallel vertical profiles. The deposit has a high degree of exploration (A:B:C1=67%:23%:10%). The study has not been certified by competent Ministry.

Balance geological and exploitation reserves of red bauxite in Zagrad deposit, status on 31 December 2006

Ore body Zagrad III

Category Balance geological reserves Al2O3 SiO2 Fe2O3 TiO2 CaO Other
A 2 533 283 60,19 2,13 20,97 2,99 0,68 12,88
B 869 206 59,65 2,58 20,81 2,98 0,60 12,87
C1 297 205 58,21 4,22 20,16 2,93 0,66 13,04
A+B+C1 3 699 694 59,53 2,38 20,74 2,96 0,66 12,81  


Ore body Zagrad IV

Category Balance geological reserves Al2O3 SiO2 Fe2O3 TiO2 CaO Other
A 89 724 59,28 3,53 20,20 2,96 0,62 13,01
B 73 850 58,67 4,36 19,54 2,93 0,75 13,29
C1 71 545 59,13 4,96 20,14 2,92 0,55 12,94
A+B+C1 235 119 58,74 4,22 19,97 2,94 0,64 13,08 


ZAGRAD TOTAL

Category Balance geological reserves Al2O3 SiO2 Fe2O3 TiO2 CaO Other
A 2 623 007 60,16 2,18 20,94 2,99 0,68 12,88
B 943 056 59,57 2,72 20,71 2,98 0,61 13,29
C1 368 750 58,21 4,22 20,16 2,93 0,66 13,04
A+B+C1 3 934 813 59,48 2,49 20,69 2,96 0,66 12,83