Geochemical Fingerprint and Iron Ore Potential of the Siliceous Itabirite from Palaeoproterozoic Nyong Series, Zambi Area, Southwestern Cameroon

Abstract

The study area forms part of an emerging iron ore province of southern Cameroon. Geochemistry analyses reveal that the siliceous itabirite has a very simple chemical composition, with Fe2O3 and SiO2 representing more than 96 wt.% of the average composition; suggesting chemical precipitates of silica and iron. Low Al2O3 and TiO2 concentrations and a weak positive correlation between them point to a minor detrital component in the precipitated marine sediments. The Si/Al ratio (average 52.7) indicates the hydrothermal origin of the studied itabirite. The Al–Si discrimination diagram supports this interpretation through the plot of all data in the hydrothermal field. The studied samples have low iron content (about 39.32% Fe), high gangue content (40.97% SiO2 and 1.3 % Al2O3) and low concentration of the deleterious elements (0.16 % P and < 0.01% S). The main gangue mineral is silica which can be efficiently removed from iron ores during preparation of raw materials for the blast furnace process. According to commercial standards for crude iron ores, it may be concluded that the Zambi iron ores are a low‐grade magnetic ore that can be profitably exploited for the production of iron for steel production.

Ore Texture, Mineralogy and Whole Rock Geochemistry of the Iron Mineralization from Edea North Area, Nyong Complex, Southern Cameroon: Implication for Origin and Enrichment Process

“…The Edea North area is located at the upper limit of the Nyong Unit (Figure 1(a)). This Unit is dominated by biotitehornblende gneisses, which locally appear as grey gneisses of TTG composition, orthopyroxene-garnet gneisses (charnockites), garnet amphibole-pyroxenites, and banded iron-formation [11] [13] [23] [24]. This Unit is of Mesoarchaen to Palaeoproterozoic [23], and belongs to the West Central African Belt (WCAB) [25] [26].…”

“…Although Cameroun is not yet an iron producer, past works and particularly within the ongoing decade have led to the discovery in Precambrian greenstones terrain of south Cameroon, of several BIF-hosted iron deposits including Mbalam [4] [5] [6] [7], Nkout [8] [9], Bikoula (www.aluvance.com), Elom [10], and Zambi deposits [11] and Kouambo deposit [12]. Most of these studies have used BIF to infer the origin and depositional environment of these iron formations.…”

Geochemical Constraints on the Origin of Banded Iron Formation‐Hosted Iron Ore from the Archaean Ntem Complex (Congo Craton) in the Meyomessi Area, Southern Cameroon

“…The acceptable contents of phosphorous and sulfur in commercial ores should be lower than 0.07% P and 0.1% S, respectively (Guider, ; Dobbins & Burnet, ). The average P content of the Meyomessi iron ores (0.19%) is slightly high but is within the acceptable levels for commercial ores (Ganno et al, ).…”

“…The acceptable contents of phosphorous and sulfur in commercial ores should be lower than 0.07% P and 0.1% S, respectively (Guider, 1981;Dobbins & Burnet, 1982). The average P content of the Meyomessi iron ores (0.19%) is slightly high but is within the acceptable levels for commercial ores (Ganno et al, 2016). Angerer et al (2012) have proposed the use of the bulk geochemical composition of iron ore to identify carbonate-or silicate-rich zones in BIF and illustrate the evolution of hypogene hydrothermal alteration zones through time.…”

“…The exploration results have revealed that the high magnetic anomalies are related to magnetite-rich BIFs, such as in the Mbalam (Suh et al, 2008;Chombong & Suh, 2013), Nkout (Suh et al, 2009) and Bikoula (Teutsong et al, 2017) areas. Moreover, new iron-rich bodies, namely, Elom (Ganno et al, 2015), Grand Zambi (Ganno et al, 2016), and Kouambo (Ganno et al, 2017), have been discovered in the Ntem Complex. The Meyomessi area, located about 30 km East of Sangmelima town, has another iron-rich body.…”