Alluvial diamond resource potential and production capacity assessment of the Central African Republic

Abstract

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A sub-national scale geospatial analysis of diamond deposit lootability: The case of the Central African Republic

“…Production figures suggest that 65-75% of diamond production comes from western CAR, with eastern CAR contributing 25-35% (Bardet, 1974;Censier, 1996). However, Chirico et al (2010) calculate that the two plateaus are similarly endowed with diamonds. This result suggests that the higher western zone production figures noted by Bardet (1974) and Censier (1996) may be a function of population density and mining intensity, as the west is significantly more populated and is known to have more artisanal miners and active mine sites than the east.…”

“…The deposits in southeastern CAR are also thought to be related to the sandstone formations, which have since eroded from this area. Only remnants of the former plateau remain in the southeast (Censier, 1996;Chirico et al, 2010). The diamonds found within these plateaus originally eroded from their primary source and were deposited within two alluvial fan sequences in CAR.…”

“…However, it is also associated with a high degree of uncertainty, as miners lack efficient exploration techniques and often operate largely by guesswork (Jønsson and Fold, 2011). It is estimated that there are approximately 60,000-90,000 miners operating in CAR (Bermú dez-Lugo, 2011;Chirico et al, 2010). It is important to note, however, that estimating the number of artisanal miners in a particular region or country is a challenging task, due to factors such as the transient nature of miners, poor record-keeping by mine managers, and the informality of the sector (Heemskerk, 2001).…”

“…These alluvial fans were subsequently re-consolidated over a period of geologic time and subjected to tectonic and erosional forces. The diamond deposits are now being re-eroded from the plateaus and reconcentrated within Quaternary floodplains and Tertiary terraces, from which they are mined (Chirico et al, 2010).…”

A methodological toolkit for field assessments of artisanally mined alluvial diamond deposits

“…• The Republic of the Congo (Barthélémy and others, 2006) • The Central African Republic (Chirico, Barthélémy, and Ngbokoto, 2010) • Mali (Chirico, Barthélémy, and Koné, 2010) • Ghana (Chirico, Malpeli, and others, 2010) • Guinea (Chirico and others, 2012) • Côte d'Ivoire (Chirico and Malpeli, 2013) Each assessment is composed of multiple components and integrates various types of data. The assessment methodology can be divided into five phases:…”