BWA Group PLC - Results of Granulometric Testwork Nkoteng Project, PR Newswire


7 September 2022


(“BWA”, or the “Company”) (AQSE: BWAP)

Results of Granulometric Testwork at the Nkoteng Heavy Mineral Sands Project, Cameroon

BWA Group plc [AQSE: BWAP], which has mineral exploration licences in both Cameroon and Canada and is quoted on London’s AQSE Growth Market, provides an update on its recently completed in house granulometric studies, carried out on 20 samples from the recently completed mechanised auger programmed, from within the Nkoteng 1 Licence, Central Cameroon (“Nkoteng 1” or the “Nkoteng Project”).

BWA currently has four heavy mineral sands (“HMS”) licences across two project areas in Cameroon, all of which are at an early stage of exploration. The Nkoteng 1 Licence covers an area of 497 km2 and the contiguous Nkoteng 2 Licence covers an area of 500 km2, located 60 km to the northeast of Yaoundé with easy transport links to the port of Douala.  The Nkoteng Licences cover significant part of the HMS prospective Sanaga river system (See Figure 1). The Dehane 1 and Dehane 2 Licences (“Dehane” or the “Dehane Project”) cover an area of 186 km2 comprising part of the prospective Nyong river system, estuary, and coastal zone, located approximately 166 km to the west of the capital, Yaoundé and 70 km from the deep seaport and industrial zone of Kribi.

BWA is pleased to announce the findings of in house granulometric and size fractioning studies from 20 samples taken from the recently completed closed barrel mechanised auger sampling programme on the Nkoteng 1 Project, reported in accordance with JORC (2012). The short shallow auger sampling programme completed in June 2022 drilled 107 holes for 193.30 metres and 171 primary samples (RNS dated 29th of June 2022). The programme targeted the central sector of the licence where pitting and hand auger sampling (BWA, 2021) identified an area of anomalous Ilmenite, Rutile, Zircon and Kyanite alluvial HMS (See Figure 2).

A selection of 20 samples from the mechanised auger programme underwent granulometric and size fractioning studies, completed by BWA using the facilities at Afrigeolabs, Yaoundé (See Figure 2 and 3). These are duplicate portions of the samples which have been selected for submission to specialist laboratory in Germany for heavy mineral separation and mineral composition testwork, currently awaiting shipment, with results expected Q4 2022.

A version of this announcement containing the maps, figures and appendices can be viewed on the Company’s website,


  • Rutile is most abundant mineral, especially concentrated within the sand size fraction -600 to +180 µm (see Figure 3). Major ilmenite was also observed.
  • Minor HMS also observed in -150 µm size fraction.
  • Minor kyanite observed in weathered clays.
  • Plastic clays contain elevated ilmenite in select areas.
  • Implications of the granulometric studies are as yet not fully recognised, although suggest distinctive mineralised size fractions and preferred host strata.


The Company are currently processing the new granulometric and size fractioning results to understand the implications. This new work will be combined with the heavy mineral separation and mineral identification testwork due in late Q3, to understand the relationships and add more information to improve the understanding of the heavy mineral deposits.

BWA are very encouraged by the presence of observed intervals of Ilmenite, Rutile, Zircon and Kyanite within the programme area, especially within the -600 to +180 µm fraction (see Figure 3).

James Butterfield, interim Non-executive Chairman of BWA, commented:

“We are encouraged by this latest round of granulometric and size fractioning results from the Nkoteng licence area, again showing the occurrence of target mineralisation from all horizons within the prospective area and supporting earlier observations.

We look forward to the receipt and interpretation of results on completion of planned laboratory sample testwork from Germany and comparison with the granulometric results for use in geological modelling and potential mineral resource estimates”.

Summary of Exploration Works

In accordance with JORC (2012) reporting guidelines, a summary of the material information used is set out below. For further details, please refer to the JORC (2012) Table 1, located in the Appendix to this announcement.

The exploration programme from which the 20 samples have been selected consisted of 107 holes for 193.30 metres and 171 primary samples, collected within the current and paleo Sanaga river floodplain (see Figure 2). The holes were mechanically drilled using a Van Walt windowless percussion sampling system with half core samples split for analysis, with the remaining half core stored in bags for reference and duplicate samples as necessary. The duplicate portion of the sample was used for the granulometric works.

The 20 samples were dried in an oven for 24 hours and then six sieves with the following mesh size were used to separate the fractions for each sample: +1 mm (F1), +600 µm (F2), +180 µm (F3), +150 µm (F4), +75 µm (F5) and -75 µm (F6). The separated fractions F1 to F5 were oven dried again for weighing (F6 did not require re-drying).

Each separate size fraction was mixed with water and panned to separate out the lighter materials such as muscovite, quartz and organic matter. The remaining heavy minerals are observed at the base of the pan for each size fraction, this was then dried.

The pink / reddish colour of the rutile makes it easy to identify in the +600 µm to +180 µm fractions within the pan and they regularly form a peripheral ring around the black ilmenite minerals (see Figure 3). In F1 and F2 fractions, the bluish kyanite is easily distinguished. Additionally, within the silty-clay fraction, minor ilmenite is observed.

The table below shows the lithology, minerals and the weight of any from the various size fractions of the granulometric testwork. The work shows that the majority of the target minerals are situated within the +600 to +180 µm fraction and is encouraging in terms of potential for heavy liquid separation of the minerals of interest, as demonstrated by earlier limited mineral separation and XRD mineralogy work completed by BWA as announced in RNS dated 1st February 2022.

Additional work is required to understand the implications for continuing exploration, as well comparing this granulometric work to the mineral separation work, expected to be completed in late Q3.

FIELD GEOLOGY (+) 1mm (+)600 µm (+)180 µm (+)150 µm (+)75 µm (-)75 µm
Pit ID From To Lith Min Wgt (g) Min Wgt (g) Min Wgt (g) Min Wgt (g) Min Wgt (g) Min Wgt (g)
NKA_163 0.10 1.60 Plastic Clay R 239 R 150 R 257 I 8
NKA_163 1.60 2.60 Sand I 14 I+R 281 I 75 I 94 I 16
NKA_078 0.00 1.90 Plastic Clay R 7 R 15 R 210 I+R 27
NKA_078 1.90 4.00 Sand R 106 R 172 R 363 R 186 I+R 200 I+R 22
NKA_124 0.10 1.90 Plastic Clay R 276 R 63 R 130 I+R 26
NKA_124 1.90 3.55 Sand R 67 R 90 R 400 R 65 I+R 91 I+R 8
NKA_148 0.10 2.30 Plastic Clay R 25 R 62 R 219 I+R 36
NKA_148 2.30 3.30 Sand 11 3 R 58 R 294 R 185 R 35
NKA_119 0.00 0.65 Sand (Secondary alluvial deposits) R 89 R 114 R 253 R 40 R 113 I+R 12
NKA_119 0.65 1.35 Plastic Clay + Saprolite R 154 R 90 R 63 I 11 I 20 I 59
NKA_166 0.10 1.20 Sand (Weathering Sand) R 38 R 133 R 368 R 78 R 108 I 99
NKA_166 1.20 2.00 Weathering Clay + Sand + Gravel + Saprolite R 78 R 168 R 253 R 31 R 99 I 27
NKA_146 0.20 1.00 Sand (Secondary alluvial deposits) R 16 R 31 R 355 R 84 R 163 I 16
NKA_140 0.05 0.90 Weathering Clay R R 55 R 294 R 43 R 68 I+R 16
NKA_140 0.90 1.40 Weathering Clay + Saprolite G 123 R 42 R 158 R 16 I 46 I 8
NKA_121 0.10 0.70 Weathering Clay R 16 R 38 R 137 R 29 R 84 I 13
NKA_121 0.70 1.20 Weathering Clay +Ferruginous concretion R 100 R 28 R 86 R 14 I+R 114 I+R 10
NKA_085 0.00 0.90 Weathering Clay R+K 16 R+K 36 R 215 R 28 R 68 I 23
NKA_085 0.90 1.40 Weathering Clay +Ferruginous concretion +Saprolite G 424 R 19 R 85 R 21 R 42 I 12
NKA_159 0.10 1.80 Weathering Clay R 23 R 36 R 146 R 84 R 211 I 69

R-rutile, I – ilmenite, K – kyanite and G – goethite.

Geology and Geological Interpretation

The prospective Sanaga river is the main river which runs through the BWA Nkoteng 1 and 2 licence area and accommodates approximately 100 km of the river floodplain system and associated tributaries, and an even larger paleo-floodplain area, observed in satellite imagery, although this has yet to be fully ground-truthed through fieldwork.

The geological sequence generally consists of a cover of clays, overlying the target deposit layer consisting of sands and gravels, generally laying directly on the bedrock.

Surficial geology encountered during the auger programme comprised of 0.2 m of surface organic rich soil, alluvial clays and sandy clays ranging from 0 m to 4 m with an average thickness of approximately 1.3 m thick, and basal sand and gravels ranging from 0 m to 3 m thick in places.

The Nkoteng deposit is likely to be a trap placer (native) deposit. The entire stratigraphic column of the Sanaga alluvial deposits is considered potentially mineralised.

Nkoteng is located within the Yaoundé Domain of the Pan African Belt, a large nappe unit that has been thrusted southward onto the Congo Craton and is characterised by low-grade to high-grade garnet bearing metamorphosed schists, gneiss and orthogneisses.

Implications for Exploration

The positive results for rutile and ilmenite content from the sampled areas are extremely encouraging and show positive continuation of mineralisation over 8 km.

BWA are extremely encouraged by the grade and extent of all the target minerals and are planning follow up work, to be conducted shortly.

Competent Person’s Statement

The information in this report which relates to exploration results for the Nkoteng Project is based upon and fairly represents information collected and compiled by Mr Emmanuel Simo, MSc., Senior Geologist and Chief Geologist for BWA, who is a Member of the Australian Institute of Geoscientists.

The results were reviewed by Mr J.N. Hogg, MSc. MAIG, Principal Geologist for Addison Mining Services (AMS) and Non-executive Director of BWA.

Mr Simo and Mr Hogg have sufficient experience relevant to the style of mineralisation, the type of deposit under consideration and to the activity undertaken to qualify as a Competent Person as defined in the JORC Code 2012 edition of the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves.

Mr Hogg has reviewed and verified the technical information that forms the basis of and has been used in the preparation of this announcement, including all sampling and analytical data, and analytical techniques. Mr Hogg consents to the inclusion in this announcement of the matters based on the information, in the form and context in which it appears.

Forward Looking Statement

This announcement contains forward-looking statements which involve a number of risks and uncertainties. These forward-looking statements are expressed in good faith and believed to have a reasonable basis. These statements reflect current expectations, intentions or strategies regarding the future and assumptions based on currently available information. Should one or more of the risks or uncertainties materialise, or should underlying assumptions prove incorrect, actual results may vary from the expectations, intentions and strategies described in this announcement. No obligation is assumed to update forward looking statements if these beliefs, opinions and estimates should change or to reflect other future developments.   

For further information on the Company, please visit or contact:

James Butterfield
Interim Chairman
+44 (0) 7770 225 253
Allenby Capital Limited
Corporate Adviser 
Nick Harriss/Freddie Wooding
+44 (0)20 3328 5656

Glossary of Technical Terms:

“%” percent;
Al2O3 Aluminium Oxide;
“ALS” Australian Laboratory Services;
“AMS” Addison Mining Services;
"BRGM" Bureau de Recherches Géologiques et Minié
(French Geological Survey);
"BWA" BWA Group PLC;
"DTM" Digital Terrain Model. Computerised topographic model;
"DUP" Décret d'Utilité Publique (Public Utility Decree);
"HMS" Heavy Mineral Sands;
“km” Kilometre;
"TiO2" Titanium dioxide, also known as titanium (IV) oxide. Generally sourced from ilmenite, rutile, and anatase;
"Zr" Zircon or Zirconium;
“JORC (2012)” the 2012 edition of the JORC code;
“JORC” the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves, as published by the Joint Ore Reserves Committee of The Australasian Institute of Mining and Metallurgy, Australian Institute of Geoscientists and Minerals Council of Australia;
“m” metre;
“ME-XRF11bE” Analysis by Fusion/XRF;
“QA/QC” Quality assurance/quality control.
“µm” micrometre or micron, unit of length equalling 1×10-6 metre