Kore Potash is incorporated and registered in England and Wales and wholly owns Kore Potash Limited of Australia. Kore Potash Limited has a 97% shareholding in Sintoukola Potash SA (“SPSA”) in the RoC. SPSA has 100% ownership of Kola Potash Mining SA (“KPM”).
KPM has 100% ownership of the Kola Mining Lease on which the Kola Deposit is situated. The Kola Deposit is located within the Kola Mining Lease. SPSA is also the 100% owner of the Dougou Mining Lease. The Dougou Mining lease hosts the Dougou Deposit and the DX Deposit.
Under the existing Mining Convention, the RoC Government is entitled to 10% ownership in the Kola and DX Projects. The transfer of this 10% awaits instructions from the Government.
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Summary:
The potash seams are hosted by the 300-900 m thick Lower Cretaceous-aged (Aptian age) Loeme Evaporite formation These sedimentary evaporite rocks belong to the Congo (Coastal) Basin which extends from the Cabinda enclave of Angola to the south well into Gabon to the north, and from approximately 50 km inland to some 200-300 km offshore. The evaporites were deposited between 125 and 112 million years ago, within a post-rift ‘proto Atlantic’ sub-sea level basin following the break-up of Gondwana forming the Africa and South America continents.
The evaporite is covered by a thick sequence of carbonate rocks and clastic sediments of Cretaceous age to recent (Albian to Miocene), referred to as the ‘Cover Sequence’, which is between 170 and 270 m thick over the Kola deposit. The lower portion of this Cover Sequence is comprised of dolomitic rocks of the Sendji Formation. At the top of the Loeme Formation, separating the Cover Sequence and the underlying Salt Member is a layer of anhydrite and clay typically between 5 and 15 m thick and referred to as the Anhydrite Member. At Kola, this layer rests un-conformably over the Salt-Member, as described in more detail below.
Within the Salt Member, ten sedimentary -evaporative cycles (I to X) are recognized with a vertical arrangement of mineralogy consistent with classical brine -evolution models; potash being close to the top of cycles. The Salt Member and potash layers formed by the seepage of brines into an extensive sub sea -level basin. Evaporation resulted in precipitation of evaporite minerals over a long period of time, principally halite (NaCl), carnallite (KMgCl 3·6H 2O) and bischofite (MgCl 2·6H 2O), which account for over 90% of the evaporite rocks. Sylvinite formed by the replacement of Carnallitite within certain areas. Small amounts of gypsum, anhydrite, dolomite and insoluble material (such as clay, quartz, organic material) is present, typically concentrated in relatively narrow layers at the base of the cycles (interlayered with Rock -salt), providing useful ‘marker’ layers. The layers making up the Salt Member are conformable and parallel or sub - parallel and of relatively uniform thickness across the basin, unless affected by some form of discontinuity.
There are upwards of 100 potash layers within the Salt Member ranging from 0.1 m to over 10 m in thickness. The Kola deposit is hosted by 4 seams within cycles 7, 8 and 9, from uppermost these are; Hangingwall Seam (HWS), Upper Seam (US), Lower Seam (LS), Footwall Seam (FWS). Seams are separated by Rock -salt.
Individual potash seams are stratiform layers that can be followed across the basin are of Carnallitite except where replaced by Sylvinite, as is described below. The potash mineralogy is simple; no other potash rock types have been recognized and Carnallitite and Sylvinite are not inter -mixed. The seams are consistent in their purity; all intersections of Sylvinite are comprised of over 97.5% euhedral or subhedral halite and sylvite of medium to very coarse grainsize (0.5 mm to = 5 mm). Between 1.0 and 2.5% is comprised of anhydrite (CaSO 4) and a lesser amount of insoluble material. At Kola the potash layers are flat or gently dipping and at depths of between 190 and 340 m below surface.
The contact between the Anhydrite Member and the underlying salt is an unconformity and due to the undulation of the layers within the Salt Member at Kola, the thickness of the salt member beneath this contact varies. This is the principal control on the extent and distribution of the seams at Kola and the reason why the uppermost seams such as the Hangingwall Seam are sometimes absent, and the lower seams such as the Upper and Lower Seam are preserved over most of the deposit.
The most widely distributed Sylvinite seams at Kola are the US and LS, hosted within cycle 8 of the Salt Member. These seams have an average grade of 35.5 and 30.5 % KCl respectively and average 3.7 and 4.0 m thick. The Sylvinite is thinned in proximity to leached zones or where they ‘pinch out’ against Carnallitite. They are separated by 2.5 -4.5 m thick Rock -salt layer referred to as the interburden halite (IBH). Sylvinite Hangingwall Seam is extremely high grade (55 -60% KCl) but is not as widely preserved as the Upper and Lower Seam being truncated by the Anhydrite Member over most of the deposit. Where it does occur, it is approximately 60 m above the Upper Seam and is typically 2.5 to 4.0 m thick. The Top Seams are a collection of narrow high grade seams 10 -15 m above the Hangingwall Seam but are not considered for extraction at Kola as they are absent (truncated by the Anhydrite Member) over almost all the deposit.
The Footwall Seam occurs 45 to 50 m below the Lower Seam. The mode of occurrence is different to the other seams in that it is not a laterally extensive seam, but rather elongate lenses with a preferred orientation, formed not by the replacement of a seam, but by the ‘accumulation’ of potassium at a particular stratigraphic position. It forms as lenses of Sylvinite up to 15 m thick and always beneath areas where the Upper and Lower seam have been leached. It is considered a product of re -precipitation of the leached potassium, into pre -existing Carnallitite -Bischofitite unit at the top of cycle 7.
The insoluble content of the seams and the Rock -salt immediately above and below them is uniformly low (<0.2%) except for the FWS which has an average insoluble content of 1%. Minor anhydrite is present throughout the Salt Member, as 0.5 -3 mm thick laminations but comprise less than 2.5% of the rock mass of the potash layers.
Reflecting the quiescence of the original depositional environment, the Sylvinite seams exhibit low variation in terms of grade, insoluble content, magnesium content; individual sub -layers and mm thick laminations within the seams can be followed across the deposit. The grade profile of the seams is consistent across the deposit except for the FWS; the US is slightly higher grade at its base, the LS slightly higher grade at its top. The HWS is 50 to 60% sylvite (KCl) throughout. The FWS, forming by introduction of potassium and more variable mode of formation has a higher degree of grade variation and thickness.
The original sedimentary layer and ‘precursor’ potash rock type is Carnallitite and is preserved in an unaltered state in many holes drill -holes, especially of LS and in holes that are lateral to the deposit. It is comprised of the minerals carnallite (KMgCl 3·6H 2O), halite (NaCl) (these two minerals comprise 97.5% of the rock) and minor anhydrite and insolubles (2.5%). The Carnallitite is replaced by Sylvinite by a process of ‘outsalting’ whereby brine (rich in dissolved NaCl) resulted in the dissolution of carnallite, and the formation of new halite (in addition to that which may already be present) and leaving residual KCl precipitating as sylvite. This ‘outsalting’ process produced a chloride brine rich in Mg and Na, which presumably continued filtering down and laterally through the Salt Member.
Dimensions
length (along strike or otherwise), plan width, and depth below surface to the upper and lower limits of the Mineral Resource. In its entirety, the deposit is 14 km in length (deposit scale strike) and 9 km in width. The shallowest point of the upper most Sylvinite (of the HWS) is approximately 190 metres below surface. The depth to the deepest Sylvinite (of the FWS) is approximately 340 metres below surface.