The Oakover East Project is located between 40km and 80km to the south of the operating Woodie Woodie manganese mine in the Pilbara region of Western Australia.

The project consists of both 100% owned and Carawine JV tenure, is prospective for manganese, copper and iron with primary focus on the Wandanya Prospect (BCA 100%) and Fig Tree Prospect (BCA 75%).

Background

Previous exploration on the Oakover East tenements has concentrated on extensive outcropping manganese at Fig Tree associated along the contact between the Carawine Dolomite and the overlying Pinjin Chert.

At Wandanya the high-grade manganese and iron appear to be related to a particular stratagraphic horizon but has similarities in terms of grade and mineralogy to hydrothermal mineralisation at Woodie Woodie.

The Fig Tree region has been the subject of previous aerial and surface geophysical surveys, mapping, rock chip sampling and RC drill testing which has provided a substantial high-quality dataset to assist in target evaluation and ranking.

Wandanya Project

The Wandanya project (E46/1407, 100% BCA) is located on the eastern boundary of the Oakover Basin about 80 km south of the Woodie Woodie Manganese mine. Black Canyon has discovered unique stratabound, high-grade out cropping manganese and iron that has similarities to the hydrothermal manganese mined at Woodie Woodie but hosted in a shallow dipping horizon. Significant drill intersects received from initial RC drilling include:

• 5m @ 31.1% Mn from surface, including 2m @ 42% Mn (WDRC005)
• 7m @ 28.3% Mn from 6m, including 5m @ 34.9% Mn (WDRC007)
• 7m @ 26.3% Mn from 2m, including 3m @ 38.2% Mn (WDRC013)
• 6m @ 26.3% Mn from 4m, including 3m @ 40.1% Mn (WDRC021)
• 6m @ 29.6% Mn from surface, including 3m @ 41.0% Mn (WDRC031)
• 6m @ 29.2% Mn from 4m, including 3m @ 39.7% Mn (WDRC032)
• 5m @ 32.4% Mn from 3m, including 3m @ 40.1% Mn (WDRC033)

The mineralisation shows consistent thickness and grades, with only 240m of strike drill tested within the 3,000m long manganese corridor identified at the W2 Prospect. The W2 Prospect represents a shallow and potentially open pittable target, with all the manganese drill intersects encountered to date within 15m of surface and most within 10m.

Associated with the manganese mineralisation are outcropping iron formations that have returned high grade assay results including: 64.3%, 62.4%, 58.8%, 58.6% Fe, 63.3%, 63.1 and 57.6% Fe. The high-grade iron mineralisation results are within the typical grade ranges for Direct Shipping Ores (DSO). Significant exploration potential exists along a 5km long striking ridge with multiple hematite rich and enriched iron formations between 50m and 300m wide, with the southern 2km hosting higher iron grades adjacent to high-grade manganese. The potential quality of the high-grade iron formations is demonstrated with low deleterious content for elements such as phosphorus, silica and alumina.

The mineralisation model at W2 is preliminary but it appears to be a fault related hydrothermal stratabound deposit. There may be a supergene overprint to the original hydrothermal mineralisation. The mineralisation is located within a sedimentary sequence.

From the base to the top of the sequence the geology comprises footwall dolomite, spotted manganese dolomite, massive manganese and manganese dolomite breccia overlain by hanging wall dolomite. The consistency of the mineralisation down dip and along strike has been interpreted to represent fault related, hydrothermal stratabound style of manganese mineralisation.

Geothite alteration is common above the manganese zone and hematite was logged within the mineralised zones as jaspilitic bands. This may transition to high grade iron mineralisation to the west at the top of the northerly trending ridge.  

Manganese intensity increases towards the base of the sequence. The overall geological sequence is dipping very shallowly to the east but is also openly folded with a northerly axial plane forming undulating outcrops.

Several large north-easterly faults can be identified along strike associated with surface mineralisation. The lithological sequence of the W2 prospect principally consists of the Enachedong Formation carbonates overlying the Stag Arrow Formation sediments from the Proterozoic Manganese Group of the southern Oakover Basin.

The mineralisation style at W2 is stratabound and maybe associated with hydrothermal fluids replacing a suitable reactive host work at the base of the Enachedong Formation. Faults and structure are considered important features of this style of mineralisation with multiple north-east trending faults visible from surface imagery.

Further drilling is required to target down dip extensions and along strike to understand and quantify the footprint of this new style of high-grade, stratabound manganese and iron mineralisation.

Fig Tree Project

The Fig Tree Manganese Trend comprises a string of prospects with potential for high-grade, hydrothermal style manganese mineralisation and being located only 35km from the Woodie Woodie Operations, has a similar geological setting with previous drilling successfully identifying the prospective manganese corridor.

Black Canyon has leveraged off the high-quality historic exploration dataset that covers the project to carefully review the geological and more importantly the structural setting of the known manganese prospect and to generate new targets for evaluation and drill testing.

The Woodie Woodie operation has a long history of discovering and developing multiple small but high value manganese mineral resources. More than 30 pits have been developed at Woodie Woodie ranging from 0.2Mt to 10Mt with an average size of 0.5Mt¹. The strategy for Black Canyon is to explore the multiple discrete known zones of manganese mineralisation and new targets that may develop into mineral resources with the application of ground geophysics and follow-up drill testing.

Surface manganese mineralisation was observed along a strike of 1,200m between the SU1 and ZL1 prospects, where previous down dip drilling intersected significant high-grade intervals, including:

• 11m @ 18.8% Mn from 66m (SU2RC001)
• 6m @ 16.8% Mn from 7m (SU2RC008)
• 14m @ 18.5% Mn from 52m including 8m @ 27.8% Mn (SU2RC011)
• 14m @ 16.2% Mn from 54m including 9m @ 21.4% Mn (SURC020)
• 11m @ 15.0% Mn from 62m including 5m @ 24.4% Mn (SURC021)
• 13m @ 13.6% Mn from 13m including 7m @ 18.3% Mn (ZLRC016)
• 26m @ 12.6% Mn from 18m including 10m @ 18.2% Mn (ZLTRC015)

High grade mineralisation was previously sampled and drilled at the HD1 Prospect. The outcrop is 170m long with a width ranging from 10m to 20m. A structurally controlled corridor from the HD1 prospect has been mapped for approximately 2,500m to the NW with three other manganese enriched outcrops also identified. A single rock chip sample was previously taken at one of the three prospects that returned an assay of 34.2% Mn (PM102265) which supports the grade potential of the additional targets. Significant previous drill results from HD1 include:

• 7m @ 33.2% Mn from 2m (HADRC017)
• 3m @ 17.0% Mn from surface (HADRC018)

Elsewhere at the Gemms, and Narn Doc Mai Prospects, numerous rock chip samples grading >50% Mn were returned that require follow up in future programs.

1. S. A. Jones (2017): Geology and geochemistry of fault-hosted hydrothermal and sedimentary manganese deposits in the Oakover Basin, east Pilbara, Western Australia, Australian Journal of Earth Sciences, DOI: 10.1080/08120099.2017.1272492 ↩︎