The Marble Bar project comprises several gold targets around the town of Marble Bar. Through several wholly-owned tenements and an additional set of joint venture agreements with the Creasy Group, Novo is undertaking systematic exploration over twenty-seven mining, exploration and prospecting licences covering about 1400 sq km.
At Marble Bar, Novo is exploring several prospects for gold-bearing conglomerates within the Hardey Formation and at the base of the Roe Formation, both part of the Fortescue Group, a thick sequence of ancient sedimentary and volcanic rocks. The Virgin Creek and Contact Creek prospects are the more advanced prospects along several tens of kilometres of underexplored outcropping conglomerate and unconformity horizons. Novo secured the Marble Bar Paleoplacer Gold project in July 2012 under a joint venture agreement and added additional tenure over time.
Other gold targets are identified within some of the oldest rocks on Earth; greenstone dating to about 3.2 to 3.6 billion years. Greenstone was intruded by granite at around 3.0 to 3.2 billion years ago, and collectively, the granite-greenstone assemblage forms the core of the Pilbara craton. Gold at Talga Talga is believed to have been deposited very early, likely before 3.2 billion years, making this one of the oldest gold systems on Earth. Novo acquired the Talga Talga project in August 2015 following a transaction with Talga Resources (“TLG”) after recognising the gold potential of the wider East Pilbara Region.
Talga Talga is a historically recognised high grade and nuggety orogenic gold deposit within the Warrawoona Supergroup and has numerous shallow historic workings. Early prospecting and mining at Talga Talga, beginning in the late 1800’s, resulted in discovery of numerous gold specimens ranging from tens to hundreds of ounces of gold. Modern prospectors using metal detectors have continued to discover large alluvial nuggets at Talga Talga in recent decades. One lode source, the McPhee’s Reward vein, is widely regarded as the principal source for much of this coarse gold.
Anomalous rock sample results all fall on several structures parallel to stratigraphy or cutting across stratigraphy at low angles. Competence contrasts within the stratigraphic package, particularly where the McPhee Formation overlies the North Star Basalt, causes flexures in the structures and generates internal variability along strike. Historical workers have been able to identify high grade components as narrow and short-lived shoots and selectively mined these from shallow shafts and adits, extracting high grade and nuggety material. The remainder of the mineralised structure and larger quartz blowouts were left behind. It now appears significant strike lengths of these shears are consistently mineralised within the host stratigraphy.
2018 mapping and sampling by Novo staff better defined a total of 2.8km of strike length including best results of 81.4 g/t, 46.9 g/t, 35.1 g/t and 30.0 g/t gold from rock chip sampling. From a total of 149 collected samples, 68 returned grades greater than 0.5 g/t gold and average 8.5 g/t gold. In all 33 samples have returned grades greater than 5.0 g/t gold and average 15.2 g/t gold.
Mineralised veins are more laminated to the southwest and transitions to more breccia and breccia margin dominated mineralisation to the northeast. Mineralisation appears related to quartz-carbonate alteration and is accompanied by minor sulfide, mostly pyrite. Visible gold is evident in many samples.
The Marble Bar Paleoplacer Gold
The Marble Bar Paleoplacer Gold Project in Western Australia is one of several gold projects that make up Novo Resource's Pilbara Paleoplacer Gold Project. At Marble Bar, Novo is exploring for gold-bearing conglomerates at the base of the Fortescue Group, a thick sequence of ancient sedimentary and volcanic rocks. Historic mines along the eastern margin of the Marble Bar sub-basin exploited pyritic gold-bearing reefs as early as the late 1800's. Otherwise, the area has seen only very limited modern exploration.
The Virgin Creek project comprises a narrow band of Hardey Formation, unconformably overlaying Roe Formation Basalt and overlain by the Kylena Basalt. The Hardey Formation in this area is a sequence of fine-grained siltstones, gritty arkose sandstones and pebble to cobble conglomerates. The conglomerates contain quartz and chert clasts that resemble some of the stratigraphy of the mineralised basement located to the north-west. Within the matrix of the conglomerates, several percent of disseminated pyrite regularly occurs, seemingly spatially associated with mineralisation.
The conglomerate unit is up to 12m in thickness with mineralisation now defined over approximately 1km in strike length. Results include 7.15m at 1.07 g/t gold from 16m drilled during the 2018 PQ diamond program, and 5m at 1.8 g/t gold from 2m and 6m at 1.1 g/t gold from 10m from 2017 RC drilling. Mineralisation is open along strike and at depth.
The unconformity at the base of the Hardey Formation is defined for at least 28km, with the mineralised package mapped over more than 15km of strike length. Learnings on sample size, methodology and lab protocol at Beatons Creek will drive cost effective exploration during the 2019 field season.
Rock samples taken at Contact Creek have defined two separate ~350m strike length of variably mineralised conglomerate with best results of 12.7, 11.85 and 9.16 g/t gold. Just nine wide spaced RC holes were drilled in 2017 with a best result of 1m at 1.56 g/t gold. A second 1,000m long trend some 4km to the south shows the potential scale of the system, with further rock sample results including 15.96 and 14.39 g/t gold. This trend is not yet tested by any drilling.
Contact Creek mineralisation is hosted within 1 – 10m thick channelised conglomerate units within the Bellary Formation at the base of the Fortescue Group and overlaying metamorphic sediments of the Lalla Rookh Formation, part of the De Grey Supergroup. The Lalla Rookh Formation hosts numerous small gold occurrences in the wider region, which are a likely source for conglomerate gold within the region.