Diamond project | ISAM Holding
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Diamond project

The concession covers an area of approximately 25 km2 and it’s located about 30 km in a straight line towards NNW of the town of Macenta and about 460 km in a straight line towards the ESE of the Guinean capital, Conakry.


The area is located within the most important diamond region of the Republic of Guinea. The history of diamond mining in Guinea began and developed in this region.


The regional and the local geological setting are highly favorable for the occurrence of primary and secondary diamonds.


The concession covers an important section of the Makona river, this river is characterized by a strong structural control which coincides with the regional diamond structures. Furthermore, it has been noted in the field an important activity of “ourpallieurs” exploiting alluvial deposits associated with the mentioned river.


The area where the concession 038/MMG/DNM/hdc/2014 is located is considered like highly favorable for the occurrence of diamonds. This statement is consistent and supported by reports from the U.S. Department of Interior and Geological Survey (USSGS); Bureau de Recherches et géologiques Minières (BRGM, France), Centre de Promotion et de Développement miniers (CPDM, Guinée) and reports of diamond mining companies operating in the area.

Photo of the river Makona, from which traces of sand wash diamonds can be found on some rocks, one of the evidences of the presence of diamonds in the riverbed.




From Conakry, the best choice is to travel by car to the concession area. Although Macenta has a small civilian airport, there are no regular flights. To access the concession the trip is of about 700 km from Conakry on routes, where you cannot drive faster than 100 km /hr. due to the state of the roads by on one side and by the other a heavy vehicular traffic.





There are basically two types of alluvial diamond deposits in Guinea related to its distance from the primary “Source Rocks”.


A) Deposits of alluvial-eluvial close to primary sources, rich deposits are found in the alluvial ” flats” of small tributaries.


B) The second type was generated by landslides reworked and deposited in alluvial ” flats” and low terraces, typically alluvial diamond deposits are distant from the primary sources. The relief rejuvenated rivers of the Atlantic drainage system has produced a third type of alluvial deposit, associated with the new reworked channels that are represented by current actual rivers (such as Makona and Mandala). This type of deposit has been overlooked and little or no attention has been payed to this target in the area.


The analysis of both the geological framework and hydrology, shows that at the area covered by the concession excellent conditions exists to explore the following targets:


A) Primary deposits (kimberlitic dikes and pipes) in the northern part of the concession;


B) Several types of diamon diferous alluvial deposits that require different scanning techniques but among which are the current channel alluvium that could be the most simple and economical to explore;


C) Alluvial at deposits at the Makona valley covered by a soft sterile layer (~ 6 m). Drilling or mechanic excavation will be necessary to reach the productive diamond layers resting over the ancient “bed-rock”. This will require greater investment efforts of money and time but the reward might be more than interesting.



Referring to the diamond concession permit the mineralization is within the “zones of spreading of Mesozoic Kimberlites and diamond placers of Miocene and Quaternary age”.


More locally, at “Prospective Area No. 4” where the concession area is placed this geologic units are distinguished:


00AR: Granodiorites, tonalites, monzogranites, biotite granites, massive amphiboles or por roblastic gneisses of NeoMeso Archaic to Late Archean age (3150 – 2500 ± 50 m.y.) .


00PR1: Granodiorites, monzogranites, monzogranites, tonalites, microtrondjemitas, diorites quartzites, quartzite gabrodiorites, orogenic syenites and related types of the Eburnean Phase, Lower Proterozoic – Lower Rifeén age (1650 – 1350 ± 50 m.y.) .


βMz: Dolerites, gabbro-dolerites, congadiabases, granophyres and rarely diorites (sills, dikes and intrusions through fractures) belonging to the magmatic and palingeno-metasomatic formations of the “Mesozoic Gondwana Phase”. (170 ± 10 m.y.)
kMz: Dikes and Kimberlitic Pipes (95 ± 10 m.y.).