OroTree manages Craton Resources which is advancing the exploration of its Alahiné gold project situated within one of West Africa’s premier goldfields of NE Guinea. The Alahiné project area covers Birimian Group rocks and lies within one of the principal gold producing structural corridors. Exploration to date has generated three significant gold in regolith geochem anomalies covering an area exceeding 20km2 with a suggested probable structural control.
The Birimian Group of Lower Proterozoic age hosts some of the largest gold deposits in Africa. Exploration has until recent years focused on the gold fields of Ghana and Mali, with Guinea remaining the least to be fully explored with the environment known to host at least 5 styles of mineralisation. Exploration at the Alahiné project has suggested 2 styles maybe present.
- Quartz vein – stockworks and disseminated gold bearing arsenopyrite with late free gold cross cutting mineralisation. Ashanti-type, Ghana
- Auriferous quartz-pebble conglomerates with strong similarities to the Witwatersrand Group deposits. Tarkwa & Teterebie, Banket Formation Ghana. Auriferous conglomerates have been observed at Alahiné and evaluation is ongoing
- Gold bearing quartzites, rich in tourmaline, Loulo-Yalea, Mali
- Gold related granite porphyry, Ayanfuri, Ghana. Mineralisation related to granodiorites has been observed at Alahiné and 200km to the southwest at Kouroussa, both have been documented with detailed petrological studies
- Gold associated with marble, Sadiola Hill, Mali. Gold mineralisation has been identified in a range of geological units with the Birimian group, the majority of these deposits are structurally controlled and in close association with major regional scale shear zones. The structural setting of the Alahiné project and early geological associations of observed during the 2018 soil sampling program are now being reviewed in the context of similarities of deposits in Mali &Ghana.