Location: Southern Serbia, 240 kilometres south of Belgrade
Ownership: Tethyan holds an exclusive Option for 100% purchase from Deep Research d.o.o. (private Serbian company)
License Area: 87 square kilometres
Primary Targets: Porphyry copper-gold, high-sulphidation gold, lead-zinc-silver veins
Tethyan Resources entered into an option agreement over the Suva Ruda project in September 2016 (see press release dated 27th September 2016), currently owned by a Serbian private company Deep Reseach d.o.o. According to the option agreement, Tethyan holds the option to purchase 100% of the project at any time during an 8 year period for a EURO 6 million cash payment provided that Tethyan achieves certain exploration and payment milestones (discussed further in the ‘Option Agreement’ tab).
Situated in in the Vardar Metallogenic Belt, an extension of the renowned Trepca mining district, historically the Suva Ruda area has been mined for lead and zinc, beginning in Roman times as is evidenced by more than 130 pits, shafts and development drives, and more recently during the 20th Century as larger open pit operations; however little exploration for porphyry copper and gold has occurred. More recently the Tulare porphyry (Dundee Precious Metals: 523Mt @ 0.24% Cu & 0.23 g/t Au) and Skouries porphyry (Eldorado Gold: 568Mt @ 0.35% Cu & 0.47 g/t Au) deposits have been discovered in the same geological belt.
Local Geology and Previous Exploration
The Suva Ruda exploration license covers Jurassic serpentinite and Cretaceous andesitic volcanics intruded by Tertiary dacite stocks. There are two well-defined targets within the Suva Ruda exploration license:
- High-grade lead and zinc veins such as those mined historically and those on the periphery of the Rudnitza porphyry; and
- A well-defined porphyry dacite stock with significant copper and gold mineralisation, named the ‘Rudnitza’ porphyry.
Phelps Dodge located the Rudnitza porphyry stock in 2004 and drilled 7 widely spaced drill holes over an area of 1.2 kilometers by 0.8 kilometers. The holes were centred on a porphyry stock with outcropping quartz stockwork occurring over an area 500 meters by 450 meters surrounded by more widely spread phyllic and advanced argillic alteration with massive silica and alunite occurring over a broader area. Three of the drill holes were drilled into the quartz stockwork and underlying potassic core, the other 4 holes were drilled on the periphery of the stock into phyllic alteration. Generally the holes were drilled to depths between 170 and 300 meters and did not test the porphyry at depth. The 3 holes drilled into the potassic core all intersected substantial mineralisation, see table 1, including drill hole PDRC 04-03 which intersected 144 meters @ 0.4% copper, 0.4 g/t gold from 100 meters and ended still in mineralisation. It should be noted that the Rudnitza porphyry outcrops as a hill which reaches up to an elevation 200 meters higher than the surrounding plain. Hence drill hole PDRC 04-03 only just intercepted the region defined by surrounding ground level, and hence any strip required in a future mining scenario will be substantially reduced.
The surface expression of the Rudnitza porphyry and initial drilling indicates that the exposed surface represents the upper portions of the mineralised system, as evidenced by an overlying, possibly high sulphidation, gold system in which drill hole PDRC 04-03 intercepted 100 meters of massive silica containing 0.4 g/t gold from surface. Thus potential exists for a heap-leach operation mining this oxide gold zone from above the main copper-gold porphyry below.
|Drill Hole||End Depth (m)||From (m)||To (m)||Interval (m)||Copper (%)||Gold (g/t)|
Table 1. Selected drill hole results from the Rudnitza porphyry, note that drill holes PDRC 04-01 and PDRC 04-03 drilled through a low grade gold mineralised silica cap from approximately 0 to 100 meters.
In addition to the porphyry type mineralisation identified, drill hole PDRC 04-04 which was drilled to the west of the porphyry intercepted significant lead-zinc mineralisation as shown in Table 2 below.
|Drill Hole||End Depth (m)||From (m)||To (m)||Interval (m)||Lead (%)||Zinc (%)||Silver (g/t)|
Table 2. Drill hole PDRC 04-04 results showing significant lead-zinc mineralisation existing at the periphery of the Rudnitza porphyry.
Phelps Dodge exited the project in late 2004 when copper was trading around US $0.80 per pound at a time when economic open-pit copper projects tended to average greater than 1% copper.
Subsequent to Phelps Dodge, Euromax held the project from around 2006 until the Global Financial Crisis of 2008 and 2009. Euromax, having completed very little work, dropped the project in 2009 to focus on Macedonia where they are developing the Ilovica copper porphyry deposit. Following Euromax, a private Serbian company held the project and explored the area for lead and zinc, prior to going bankrupt and losing the license.
Suva Ruda occurs within an historical mining district and has excellent infrastructure. The town of Raska located near-by hosts a potential workforce and the area has abundant water and grid electricity. The area is also serviced by a railway with connections to ports located on the Adriatic Coast. In addition, the Serbian Government has declared porphyry copper-gold projects to have a high priority for development and any potential project is likely to receive strong governmental support.