The following are selected translations from various papers done on the Manono Kitolo pegmatite along with some comments. The french text is translated with google translate with some basic improvements I made (I only understand very basic french). I will jump in with comments from time to time in italics, so remember anything in italics is my own comments, not from the authors.
Please note that mineral exploration speculations in the DRC come with exciting geological upside but also associated political risks and you should do your own research, this is not investment advice.
“Expertise Géologique, Etude Mineralurgique Préliminaire Et Approche Economique En Vue De L’Exploitation Eventuelle De La Pegmatite Dure De Manono”
By J.P Bassot, M. Morio and M.X Leveque of the BRGM, Bureau de Recherches Géologiques et Minieres (Geological society of France), for the Government of Republic of Zaire, in the early 1980s.
I found this to be a fantastic document because it contains a good overview of the resource potential. Much of Geomines historical studies were focused on either the feasibility of hard rock exploitation of Tin resources (no regard to lithium) or feasibility of exploitation of lithium in tailings via conversion to carbonate.
This paper is virtually the only place you can find someone qualified taking a good look at the spodumene in hard rock, which is what we are interested in.
“At the request of the Zaire Government and within the framework of the technical assistance agreement between the Zaire State and the BRGM. J.P. BASSOT, geologist, and M. MORIO, mineralurgist, carried out an appraisal mission on the Manano deposit from 17 November to 1 December 1975
The aims of this mission were to:
- collecting information to update the knowledge on cassiterite pegmatite from Manono
- take samples to study the distribution of various mineralizations
- carry out a first ore sampling in order to carry out a preliminary mineral investigation
In this report, after a brief history of the discovery of Manono pegmatite and its exploitation to the present day, the reader will find:
A chapter devoted to the geology of the deposit where its main characteristics (geometry, grades, mineralogy, etc.) are recalled and specified. Assumptions are made about the shape and genesis of the deposit and some suggestions are made to improve the knowledge of pegmatite and its possible extensions.
A chapter devoted to mineral processing, which presents the results of the preliminary studies carried out on two large batches taken, one in the "hard rocks" quarry, in the “quarry of the 6th”, As well as on three specimens (hard rocks, block and cuttings of the quarry of M'Pété)
The results obtained make it possible to specify some basic data: contents of cassiterite and spodumene, mesh liberation of these minerals, work index of the ore.
Naturally, all these conclusions will have to be confirmed by a detailed mineralurgical study, carried out on the basis of representative samples taken from favorable zones previously recognized by a survey.
This geological and mineralurgical study has been supplemented by an economic experiment, which can not claim to draw any conclusions on the profitability of the exploitation of unaltered pegmatites; indeed, too great uncertainties exist As well as on economic data: cost of investments and operating costs in the context of North Shaba. This economic overview nevertheless confirms that the study of the exploitation of hard rocks deserves to be pursued and deepened.”
At this stage I thought I will insert two detailed maps, one of the Kitolo pegmatite and one of the Manono pegmatite so that you understand the areas being referenced.
The “Hard Rocks” quarry which will be referenced many times is known as “Carriere Roche Dure” or “Carrier R.D” in the kitolo map.
Note that the legend of the Kitolo map shows a resource estimate for Carriere R.D of 11.3m3 + 14.2m3 + 10.8M3 = 36.3m3, times an SG of 2.8 (estimate) gives you about 101.64MT of ore in Carriere RD alone. Note that Carriere RD measured is just the criss-crossed area.
“Quarry of Mpete” is as labelled and is the small area marked with a 2. Spodumene rich tailings are the “Tailings Laverne Roche Dures”, which are just south of Roche Dures or “hard rocks”.
On the manono side the “quarry of the 6th” is the area marked as “Carriere VI”, “kahungwe” is to the west. In between the two bodies is the lakushi lake. These maps are from archives in belgium.
Back to the research paper, on the history of Manono:
“2. 2 - DEVELOPMENT OF OPERATIONS UNTIL THE INDEPENDENCE OF ZAIRE
The first production dates from 1919 and the operation was carried out during the first years with modest means; After the discovery of the altered pegmatite in 1925, the leaders of Géomines had the merit of realizing that they were dealing with a very important deposit and decided, at the cost of a great financial effort (in 1932, the debt of the company was Of 35 million Belgian francs at the time), to equip it accordingly: as early as 1935, the first large mechanical shovel was used, while the first section of the Piana hydroelectric power station (3 groups) Of 5,000 KVA) was completed, thus enabling almost complete electrification of the plant and the construction of a smelter, from 1940 to 1945 the majority of cassiterite production in the Belgian Congo was treated ( 15 000 tonnes / year).
In addition to the laundries
(this refers to tin processing equipment I assume), various workshops (including a steel foundry and an oxygen factory) were built, vocational schools, hospitals and housing for 2,500 indigenous workers and 250-300 expatriates to work and live Quasi-autonomy.
Until 1949, only the eluvions and the altered parts of the pegmatits were exploited: it was the fine period of the mine, whose production reached 3500 t / year of tin (5000 tons of cassiterite at 72% Sn): Columbo-tantalite was extracted from concentrates as early as 1934 (50 to 100 tons / year). The ore was easy to process and to process, with a relatively rich content (in 1949, cut-off grade 400 g / m3 Sn02, average grade 1300 g / M3). Considering the residual contents observed in the heaps of the time (150 to 400 g / m3), it seems that the treatment was carried out with a certain laxity.
This led to the production of about one-third of Congo's tin production. From that time on, the leaders of Geomines, under the impetus of Mr. LANDA, approached the future of the deposit by exploiting stony pegmatites and hard pegmatites:
- Stony pegmatites are partially disintegrated rocks, the exploitation of which requires mining and light grinding. They currently provide a significant part of the production;
- An attempt was made to exploit the hard pegmatites between 1951 and 1956. This operation, the current president of Zairetain, Mr CLAEYS, was responsible for the operation, and was located in the western part of the deposit (Kitotolo sector) (
this area is known as “Roches Dures”)
- Three million m3 were excavated and treated
The average extracted content is 1.6 kg / m3 Sno2, while that of the treated product is of the order of 2 kg / m 2 Sno2. The residual contents determined in the heaps of the "hard rock" mining confirm the poor recovery.
According to Mr. CLAEYS, this poor performance would come from a poor study of the engineering of the treatment station rather than the flow sheet itself.
(This is an important point, the recovery could be improved)
In any case, this trial was deemed unprofitable and interrupted in 1956. It must be remembered that at the time the soft ore reserves were still important, that tin prices were (Between July 1956 and March 1957, the floor price was 640, the ceiling price of 800 pounds per tonne) and the political situation of the country became more uncertain.”
“2.3 - EVOLUTION AFTER INDEPENDENCE
The exploitation of Manono experienced various avatars at the time of the troubled period following independence, and in particular the Katangese secession.
Situated in the zone of influence of the Balubakat, Manono was the scene of fighting between the Baluba hordes and the katangai troops, then between these troops and the UN forces. Some time later, it was on the verge of multi-raid incursions and had to be protected by the mercenary forces and those of the A, N, C.
It must be pointed out that despite these troubles, there was little human or material damage, which was unfortunately not always the case at that time in Zaire.
In the following years, production was assured only at the price of a very "opportunistic" exploitation, attacking the wealthiest sectors in bad times and returning to the average minerals when the price rose. This way of operating explains the turbulent topography of the farms.
From 5,000 tons [cassiterite] in 1849, production fell to 2,710 tons in 1965.
The arrival of General MOBUTU in 1865 was followed, two years later, by a reorganization of the mining industry in Zaire; The Manono deposit was 50% owned by Zaire and a new Zairean company was incorporated on 16 October 1968. Its share capital (5 million zaire) is divided equally between the two companies, Zairean State and Geomins, A technical assistance contract binds Zairet and Geomines; The latter company assumes the technical responsibility for the exploitation and marketing of the production.
Despite these provisions, production continued to fall and the fall would accelerate after 1970”
Comments from authors on historical studies done before them:
“the flat of the Lukushi does not seem to have been seriously prospected.”
“In these studies, Manono pegmatite is conventionally considered as a multi-branched dyke or laccolite, extending 14 km along a NE-SW axis (in agreement with the direction of the host micachists) and presenting in its middle a hiatus of 2.5 km. The width of this body varies from 50 to 800 m, with an average of 400 m. The SW (Kitotolo) area has an area of 1,350,000 m2 while that of the NE part (Manono) is 1,200,000 m2.”
These dimensions are enormous. If you assume a depth of just 50m, noting that it has been drill tested to 100m ending in mineralisation, you get a volume of 127.5m3 of volume, multiple by 2.8 and that’s 357MT of ore assuming spodumene mineralisation throughout. And that number doubles for every 50m of depth and consistent thickness proven. Obviously just an exercise in big numbers but the site has huge scale.
“The accessory minerals, apart from spodumene (which can constitute up to 25% of the rock) and, to a lesser extent, cassiterite linked to the albitic phases and the greisens, are rare or even exceptional: this is the case For the usual minerals of pegmatites such as tourmaline, beryl and apatite. The absence of tourmaline is all the more remarkable in that the mica-makers are intensely tournalinized (very thin black shorl) near the contact. Columbo-tantalite is related to albite phases, but is rare in greisens; Finally, sulphides (lollingite and, to a lesser extent, pyrite) are common in unaltered rock.”
Their own observations on the geology of Manono:
“3.2.2. 1 - It is admitted that the pegmatitic body of Manono consists of two parts separated by a "hiatus" of 2.5 km this is not exact: we could indeed observe that in the "hiatus" of the pumping station located in the middle of the Lukushi dam, the pegmatite has spodumene outcrop.
At this point, it is associated with a grayish oriented granite which, under a microscope, reveals to be an albithic granite with muscovite and spodumene (mineralized notably in SnO 2: 370 g / t). For P. PICOT, who made the petrographic study, this granite is analogous to those which generally accompany the greisens.
The hiatus corresponds to a zone covered almost entirely by the alluvium of the Lukushi under which the substratum is not altered during the systematic prospecting, which was concerned only with altered eluviations and pegmatites, this zone did not Therefore not considered to contain exploitable mineralization. This does not prevent pegmatite being present and the fact that it is associated with albite granite may suggest that we are in a deep part, somehow in the roots of pegmatite”
“In the "hard rocks" quarry, some drill holes have crossed up to 75 m of pegmatite without reaching the wall. On the other hand, if we assume that the southern edge of the quarry corresponds to the roof and that the roof is placed along a slope parallel to that of the wall, it can be estimated that the thickness of the laccolite is at this point In the order of 150 to 200 m. "
“Finally, note that locally, if we believe the outcrop of the pumping station, pegmatite can be "rooted" on granite, with a transition zone rather blurred, in this case it becomes rather difficult To define the notion of thickness of the pegmatitic body.”
“3.2.3 - Zonality and petrography of the pegmatitic body
It takes a certain time to the visitor to see, if not understand, the zonality of the pegmatite of Manono.
This deposit is indeed very different from the usual zoned pegmatites, vein bodies with a few meters of power, often heavily sloped, where marked minerals (tourmaline, apatite, beryl, biotite, etc.) clearly mark the zonality.
In Manono, apart from spodumene, colored minerals are very rare; Moreover, the size of the pegmatite prevents an overall view, but, by habit, zonalite is sought in the horizontal sense, the sloping character of Manono's laccolite induces a vertical zonality.
It should also be borne in mind that almost the entire body is formed of a rather homogeneous rock with microcline, albite and spodumene, with rather rare micas.
The well differentiated facies (greisens and albite aplite) represent only a very small volume, rather irregularly distributed.”
Here I’ll insert some photos taken from the rocks in Quarry 6 and M’pete. Some are from the paper, and some from the library in Belgium:
These are pegmatite boulders from Quarry 6, showing large visible spodumene crystals:
Another photo from Quarry 6, in the “North Flank” which I assume means north wall. The crystals are not discernable here but are reportedly enormous:
More visible spodumene in Quarry 6, very large size crystals, not as big as earlier but still prominent:
An example of smaller size spodumene crystals mixed with quartz / albite:
This is a sketch of exposed rock in M’Pete, which shows again a significant proportion of spodumene as % of visible surface area:
On to the next sections:
“3.3 Distribution of Mineralization > 3.3.1 Cassiterite > 3.3.1.2 Greisens
(Looking at Cassiterite located in the greisens)
“The exogreisans are preferentially located on the roof of the pegmatite, of which they may constitute the outermost part. This is the commonest observation; The greisified layer is more or less well-defined, it can have a thickness of up to 5 to 10 m.
Exogreisans may also be located in the surrounding micachists, but in the immediate vicinity (less than 10 m) of the pegmatite: this is clearly illustrated by the old drill holes in the "hard rock" quarry, in particular the RdG8 and the RdF9. The power of these greisens must be quite variable (0.50 to 4 m). Unfortunately, we have little information on their geometry.
In general, these exogreisans are remarkably well mineralized since the contents we have available exceed 20 kg / m 3 (
Tin Grade), in order to reach, in the borehole
RdF9, the extraordinary value of 276 kg / m3 (
Insanely High Tin Grade). According to what has been said, the greisified zone on the northern flank of the quarry of the fifth would have furnished, monthly prolonged monthly production exceeding 100 tons of cassiterite. We do not know if other greisified areas have been recognized by sampling (apart from the one traversed by RdF9). The question may be raised as to whether these greisified zones could have volume / volume ratios which can be regarded as small unitary deposits.
These greisens sound very interesting. Based on that outstanding grade of tin, I thought it would be worth seeing the cross-section of the RDF9 drill hole. Note the yellow is weathered pegmatite been removed in prior mining, red is hard rock pegmatite mined briefly:
More on Tin Grades in Greisens, would be outstanding if more of these pods could be discovered, there's plenty of pegmatite to find it in:
Sondage RD FA 9 is the drill hole I put above.
Back to the paper:
“In any case, the greisens being inside the pegmatite, do not pose the problem of a separate or selective exploitation.”
3.3 Distribution of Mineralization > 3.3.1 Cassiterite > 3.3.1.4 - Pegmatite with microcline and spodumene partly albitized
(Looking at Cassiterite located in the spodumene areas)
“As we have seen, it is the rock which constitutes, from the point of view of volume, the largest part, and by far, of the pegmatitic body of Manono.
Our studies confirm previous publications, namely that cassiterite is closely related to the late silico-albicidal phase, which has reshaped the formerly crystallized stocksclid of microcline and spodumene.”
“We have several analyzes on this facies, two of which are obtained from relatively large representative samples (see chapter '' Mineral processing '').
(This refers to samples D and E)
In addition, a geostatistical study was carried out on the results of the cassiterite assays obtained on the cores of the drill holes carried out between 1949 and 1951 at the location of the "hard rocks" quarry.”
“The average grade was set at 2.2 kg / m3 Sno2. Figures very close to those accepted by the operator 2.1 kg / m3. Reserves from the area surveyed are estimated (from surface to 80) to 12 million tonnes of ore, or 26,500 tonnes of mineral. It appears, on the other hand, subject to verification by three new holes, that a 100 x 100 m probescale would be sufficient to explore other areas of microcline and spodumene pegmatite.”
“If we compare this average of 2.2 kg / m3 with the results obtained by chemical analysis on six other samples (see Figure 22), it should be noted that, apart from two samples from the quarry of 6 and M'Peté, these "chemical" contents are much stronger. This would confirm the loss of fine cassiterite, probably higher than expected.”
(The assay method used for the drill holes appear to have not tested up to 40-50% of contained tin”
“This problem, which will be dealt with more seriously in the chapter on "Mineral processing", deserves particular attention.”
“It would be interesting to multiply the tin grade on the microcline and spodumene pegmatite bodies outside the "hard rocks" quarry.”
(To derive a larger tin resource estimate)
The results shown in the table in Figure 22 show that the contents of more than 2.2 kg / m3 can be found outside this quarry and it would be preferable to be better informed on the cassiterite contents of the other sectors before deciding definitively of the location of the future exploitation in "hard rocks”.”
Tin grades throughout samples they took on site, refer to the map to understand location of each:
Clearly the tin grades alone in the hard rock pegmatite are not high enough to warrant exploitation, but perhaps with lithium having much higher economic value the story has changed.
3.3 Distribution of Mineralization > 3.3.2 Niobo-Tantalates
“LANDA, KARPOFF and CLAEYS (1950) indicate that in ordinary microcline and spodumene pegmatite, columbo-tantalite accounts for 5% of the cassiterite content, whereas in the greisens the proportion falls to 1%. However, it is not clear whether, due to the general increase in tin content in the greisens, the content In columbo-tantalite remains comparable to that of pegmatite.
For the same authors, the ratio Ta2D5 / Nb2D5 can vary from 0.66 to 1.18.
H. BERNARD (1954), who has studied soundings in the hospital sector, indicates that niobo-tantalates can represent up to 20% of the cassiterite concentrate and that the proportion of Taz05 / Nb2D5 varies from 1, 2 to 1.8 ,.
In Manono, we were told that the hospital sector was particularly rich and that at one time it extracted up to 25 t / month of columbo-tantalite.”
I believe the hospital sector is just north of the “Carriere Est”
3.3 Distribution of Mineralization > 3.3.2 Spodumene
“In view of the analysis (1.70% Li20 for a spodumene containing 6.36% Li2O) carried out on the large sample D taken from the "hard rocks" quarry, it seems that the figure of 25% Publication of LANüA, KARPOFF and CLAEYS for the content of spodumene, is verified.
Again, it is regrettable that the 1949-1951 drilling has not been better exploited because they would have given a good idea of the distribution of the lithium contents. According to the aforementioned authors, it seems that in the most weathered parts of the pegmatitic body there may be an alteration of spodumene in kaolinized products where the Li2O content drops to around 1.00%.
Taken 10 km more from E.NE, in the quarry of the 6, sample E shows a content of 31.5% of spodumene (2% Li2o).
If we consider that samples D and E do not appear to be richer in spodumene than the rock face observed throughout the body pegmatitiae, whether in the "hard rocks" quarry, or in M'Peté, On the 5th Quarry, at the 6th quarry, in the quarry of the East and Kahungwe, one can only be convinced of the enormity of the stock of spodumene present at Manono!
This is a crucial visual indicator, they believe the samples they took do not appear richer in spodumene than that seen throughout the Manono Vitolo zone. Refer to the maps above.
Let us recall in passing that the piles of the exploitation "hard rocks", that covered to 2 million m3, that is to say 7.86 million tons, thus contain approximately 1.96 million tons of spodumene, theoretically crushed to 3.2mm (in reality, in A little coarser). This figure is undoubtedly to diminish a little because of the fat that in the upper part of the quarry, there could be some alteration of the spodumene.”
This is referring to tailings produced in the attempt to mine tin from hard rock, which left some spodumene rich tailings. Of the tailings inventory of roughly 80-100MT at Manono-Kitolo, it appears only a small amount limited to this dump are rich in lithium.
3.4 CONCLUSIONS
“1 - The cassiterite contents of the "hard rock" carriers may have been underestimated: it would be interesting to double three of the former drill holes, for example C7, D8 and E8, with new drill holes to be drilled Per 2m passes, each core, divided lengthwise, being analyzed for Sn, Nb-Ta, Li and studied petrographically,
These three surveys would provide new data that would probably correct the results of all 39 previous surveys.
2 - It is not certain that the microcline and spodumene pegmatite of the quarry '' hard rocks '' is the richest in cassiterite of all the deposit. Other areas where this rock face is also well picked seem as rich (M'Peté, career of the 5, career of the East). This would have to be checked by sampling before deciding on the location of the future operation.”
This is very promising, because you can expect similar or better tin grades in spodumene throughout pegmatite.
“A) When the future exploitation of hard rocks is to be established, it will be necessary to verify by a few deep holes (100m-150m) that the volume of pegmatite expected is well under the feet. For the moment, for example in the quarry "hard rocks", the greatest demonstrated pegmatite depth is only 70 m.
(B) It is to be hoped that, in the south and north of the present estates, the principal pegmatitic body or a parallel vein will return near the surface by means of a parallel curl to that corresponding to the present holdings. Such a "wrinkle" would be interesting, not by the presence of new tonnages of microcline and spodumene pegmatite, but by the possibility of the existence of rich mineralized zones by greisinification and albitization at the top of the new cupolas or wrinkles.
Finding high tin grade greisens would be an outstanding boost to economics.
In practice, this search for extension should be carried out by geophysics (seismic or resistivity), the results of which should be verified by sampling or sinking.
In the hospital sector, the areas with greisens highlighted by the surveys studied by H. BERNARD should be followed also by sampling.
The selective exploitation of new greisified areas could be facilitated by a study of the farm archives, with a view to trying to find the characteristics (content and geometry) of the former greisens exploited. This study would give a better idea of the objective to be sought.”
Now I’ll jump to the end of section 4 which is a series of met testing on the samples D and E, sample D from Roche Dure / “Hard Rocks” quarry, and Sample E from the Carriere 6.
4 - Mineralurgical Study> 4.6 - Conclusion
The primary purpose of the preliminary mineral investigation was to acquire a good knowledge of the ore as a function of the two faces, and to determine whether the results of the first mineralurgical tests suggest that cassiterite can be properly concentrated, as well as spodumene.
However, given the very low cassiterite content of the whole and the masses of samples taken from the field (about 150 and 167 kg for the two large batches), the balances presented in this report can not, In any case, representative of Manono pegmatite, but only indicative.
All the conclusions below should be systematically checked from a representative sample, the study was carried out mainly from two voluminous samples, one from the "Roche Dure" quarry, Operated between 1950 and 1956 (sample D), the other from the "Quarry of the 6" (sample E).
Macroscopically, the texture of these two samples is very different, but the results of the chemical and mineralogical analyzes show that they are of the same composition: quartz-plagioclase-spodumene-micas.
The Li2D content makes it possible to estimate the proportion of spodumene for each of the two batches:
Sample D: 26.7% spodumene
Sample E: 31.5% spodumene
The cassiterite content of this pegmatite is confirmed to be very low: 1587 and 1105 Sn02 respectively for the D and E ores. However, the appreciable proportion of colombo tantalite relative to the cassiterite of the order of 10% must be noted, In a more detailed study, these elements (Nb-Ta) should be systematically assayed.
Only the measure of the Bond index (Work Index) translates this different texture:
For the "Roche Dure" sample, Wi 12.6 kWh / short ton
For the "Carrière 6" sample, Wi 17.9 kWh / short ton.
The granulodensimetric analysis carried out in dense liquor (tetrabromo 1,1,2,2, pure ethane d = 2,95 and pure diiodomethane d = 3,31) on the ores crushed respectively at 10 mm and 4 mm allowed To demonstrate that the release mesh:
- cassiterite is around 630 microns
- spodumene is below 630 microns
For the two minerals D and E.
Nevertheless, the results presented in Tables 27 and 28 below show that:
- For sample D, grinding to 4 mm is sufficient to recover 80.0% of the cassiterite in the heavy fraction, and 68.6% of the spodumene at a content of 6.24% Li2o in the intermediate fraction 2.95
- For sample E, grinding at 10 mm already allows 84.3% of the cassiterite to be recovered in the heavy fraction and 65.0% of the spodumene in the intermediate fraction, but a grinding at 4 mm improves the results
By allowing 83.9% of the spodumene to be recovered at a content of 6.62% Li.sub.2 O in the intermediate dimeimetric fraction, the cassiterite recovery not being evolving.
Taking into account these balances, it will be important to know whether a grinding at 3 4 mm and a recovery of cassiterite on the order of 80% are economically more advantageous than a finer grinding aking it possible to improve the recovery of cassiterite by 10 to 15%.
Note ; It should be noted that these figures do not take into account the mixed cassiterite-gangue grains present in our heavy fractions.
Simultaneously, a finer grinding will allow a better release of the spodumene.
Nevertheless, if the question of the concentration of spodumene is to arise, it will be necessary to study the possibility of carrying out a concentration (or pre-concentration) of this mineral by gravimetric separation in dense medium, a technique requiring a granularity ore greater than 500 μm.
In conclusion, the main facts or impressions which emerge from this preliminary study, carried out on very punctual samples of the Manono deposit, are:
- the low cassiterite content of the ore, but also the appreciable presence of colombo-tantaifte (10% of cassiterite) and spodumene (25 to 30% by weight of the whole)
- a priori, the grinding mesh retained in the treatment scheme installed in the quarry "Roch Dure-" in 1950 seems to correspond well to the ore to be processed, provided good production of a mineral - 3.2 mm. However, finer grinding will release more cassiterite and improve recovery. A brief economic study should make it possible to say whether the extra cost of grinding (between 4 and 1 mm, for example) would be offset by this increase in cassiterite and colombo-tantalite recovery.
- the few differences between the two samples D and E (cassiterite content, crushability, crushability, cassiterite release) will have to be studied more closely before choosing the type of ore to be exploited first.
In summary up to 84% of tin reports to concentrate grading up to 57.9% SnO2, and up to 83.9% spodumene reports to concentrate of grading up to 6.82% Li2O.
Table below shows the variance using different grind sizes. These are promising results for basic heavy liquid testing, further grind size optimisation is required and a flotation stage will add further improvement.
Assays for samples D and E:
Appendix 10:
GEOSTATISTIC STUDY OF THE K TOTOLO SECTOR J.P. MARBEAU
This is a geostatistical study done on the reported tin grades from the historical drill holes done in Kitotolo sector. Unfortunately they original assay method appears to have been unreliable in that it did not detect the finer grained cassiterite which is 40-50% of the cassiterite in the rock. The author basically says, don’t trust the data. These assays were done in the 50s, seperate to the assays done in the 80s by Bassot and Co.
While the tin assays are unreliable (note - unreliable as in the reported grade is too low). The interesting part is the visual log recording the presence of minerals in the drill core cuttings, the total count for mentions of minerals in the visual logs are below:
Cross sections where for drill holes that this logging was done:
Top down view of the drill plan, this area should correspond to the criss crossed area in the Kitolo map above:
This visual logging is another significant data point supporting huge amounts of spodumene mineralisation as expected by Bassot.
Now some excerpts from:
Mission de M. Sterpin a Manono du 26/1 au 17/2/82: Rapport De Mission
In this paper Sterpin discusses his hypothesis and consequences for the orebody:
In the longitudinal direction, ie S-W, N-E, it is possible to design the deposit as one and the same pegmatite lens seating at the S-W as at the N-E and connecting under the flat of the Lukushi.
In the transverse direction: The northern vein of Kitotolo may represent the northern flank of a synclinal pattern, and the southern vein, the summit zone of the adjacent anticlinal pattern (Fig. The whole synclinal zone being represented by the schists of the roof.
Mineralization could extend further north and south of existing quarries.
- In the north, in the form of eluvions and perhaps pegmatite islets covered by more recent sands and in the form of pegmatites under the hill of Manono.
- In the South, in the form of non-outcropping pegmatite with sub-crop.
The maximum lateral extension known at present (± to the RMB section at Manono) gives a length of + 1 km. On this distance, pegmatite has a thickness which varies from ± 20 m to the north at 80 m minimum where it appears for the moment the thickest (on the southern flank). By extrapolating the same extension further south, we find ourselves beyond the heaps and sands of decantation.
The rare grade data on the southern flank, where they are generally considered to be low grade, seem to show a marked increase towards the south. More at S-E again, the results of the previous surveys could indicate the passage of the lens or another between the Luninga and the Kalongo (Figure 6).
This hypothesis, to be checked by further work, opens up, if it proves to be accurate, new possibilities for the future of Manono.
Indeed, the potential extensions of deposits lie laterally and its characteristics, which could be very similar to those which exploitation has hitherto encountered, appear therefore to be more favorable than the characteristics of an extension at depth (hard rocks).
Here he’s saying you can probably find more weathered pegmatite material for easy tin mining like in the 40s - 60s. They were most interested in the weathered material back then, still interesting implications for the overall size of hard rock pegmatite.
This is a diagonal cross section he drew from the bottom to top.
This is a cross section on the manono pegmatite utilising historical observations made at the “hospital sector”:
This is a cross section on the kitolo side which also shows the steep dip in historical drilling and the laterite material to the north west (weathered previously outcropping pegmatite):
Cross section of Kahungwe:
Another nice picture based on same hypothesis:
Exciting implications but an untested theory.
Continued in next reply.
