Location
Sinjakovo
Republic of Srpska, Bosnia & Herzegovina
Exploration
Fe, Cu, Zn, Pb, Co, (Ag, Au)

About the project

The Sinjakovo Project is located 3 km to the south of Mrkonjic-Grad and 45 km, as the crow flies, south of Banja Luka, the second largest city in Bosnia and Herzegovina and the capital of Srpsksa. The project is accessed via tarred road from Banja Luka (60km to the north) or Sarajevo (180 km to the southeast). Lykos believes that there is significant potential for discovery of economic copper mineralisation, as well as economic barite, lead, zinc, silver and potentially gold and cobalt mineralisation at Sinjakovo.

Historical mining within the Sinjakovo licence targeted the copper-iron mineralisation hosted in siderite layers within the Carboniferous sediments and ceased in the early 1900’s. Subsequent exploration has confirmed the presence of the copper and iron mineralisation at various localities along the exposed strike of the outcropping siderite layers.

Importantly, it appears that Pb, Zn, Co, Ag and Au were not assayed and should be included in any exploration going forward. Historical samples collected from the area around the old mining operation were reported to contain elevated Ag values.

Copper and Iron Mineralisation

Historical mining and exploration activities identified a number of mineral occurrences within the Sinjakovo licence area and include the copper-iron mineralisation within the Carboniferous schists and limestones which outcrop in the centre of the licence and barite hosted lead-zinc-copper-silver mineralisation in the Devonian age sediments which outcrops in the southwest and east of the licence.

The early mining activities targeted the chalcopyrite-bearing siderite-ankerite layers within the Carboniferous schists and limestones for the iron around the Ravni Osredak locality in the centre of the licence area. Subsequent mining by the Austro-Hungarians from 1894-1910 targeted the chalcopyrite mineralisation associated with the siderite layers.

Historical accounts indicate that during the Austro-Hungarian mining between 27,000t and 120,000t grading between 3-25% Cu were mined. Material grading less than 3% Cu was considered waste at the time and used to backfill tunnels or stockpiled at the portal. Historical work estimated that between 15,000-16,000t of copper-iron mineralised material remains outside of the historical mine portal. The chalcopyrite forms layers, ranging between 2m and 6.5m, mostly within a series of siderite-ankerite bodies/layers, which vary between 1m and 30m thick, averaging 15m. The siderite-ankerite mineralisation has been mapped for approximately 2km as a series of concordant discontinuous lens shape and faulted layers along a Z-shaped curvilinear trace with potential strike extents to the northwest and east of the mapped outcrops, under the younger Triassic cover.

Barite Hosted Pb-Zn-Cu-Ag Mineralisation

The barite is hosted within Devonian age limestones which outcrop in the east and northeast of the licence area as well as just outside the eastern edge of the licence near Jezero. The barite occurs as either:
  • “first generation” veins associated with quartz and range from a few centimetres to tens of centimetres in width and are thus of limited economic significance, or as

  • “second generation” barite associated with sulphides, usually tetrahedrite ((Cu,Fe,Zn,Ag)12Sb4S13).

This material was mined in the past on a small scale at Otomalji mountain, <1km outside the eastern border of the licence area. Within the licence area there are several old adits at the locality D Jumezlije and Beg Luka (1km NNW of Jezero town) (Figure 5.4.2) on the left Josavka riverbank and barite (with malachite and azurite) can be found on the dumps. Another locality with 6 a dits, 1km to the NW of D Jumezlije, was also mined. Here outcrops of barite, ~25cm thick and dipping at 60° to the west contain galena veins and can be traced for 50m. Further to the northwest a number of barite occurrences and old workings are also found. Various samples taken f rom these occurrences during the exploration by the Yugoslav Geological Survey between 1988-1990 elevated Pb, Zn, Cu and Ag. Many of these are proximal quartz porphyry intrusions and consistent with meso-epithermal mineralisation.