West Africa-focused explorer Genmin (ASX: GEN) has achieved premium iron grades from commercial-scale pilot plant testwork on an initial five bulk samples from its wholly-owned Baniaka project in the Republic of Gabon.
Conducted in South Africa by specialist mineral processing and engineering firm Bond Equipment, the large-scale testwork aims to develop engineering level process design criteria and confirm product yields, grades and quality for the project.
Genmin has also provided two 700kg lump and fines product samples to China’s Central South University for value-in-use testing at the School of Minerals Processing.
The testing will help populate a financial model to be included in the Baniaka pre-feasibility study, relating to price differentials for Genmin’s products and to provide steel mills with initial exposure to Baniaka’s production.
Mineral resource envelope
A total of 13 samples were sent to Bond for pilot plant testwork from within Baniaka’s mineral resource envelope across the Flouflou, Bandjougoy, Tsengué, and Bingamba North prospects.
Seven were representative of the project’s detrital iron deposits (DID) and six were oxidised Banded Iron Formation (soft and intact oxide), for an approximate total wet weight of 22.4 tonnes.
Results have been received for three DID and two soft oxide samples to date.
The DID samples returned premium lump and fines grades of 64.1% and 65.1% respectively, and a high average lump yield of 42% with an expected lump-to-fines ratio of 42% to 58%.
Iron head grades for the same samples returned an average 114% uplift on the target sample zone head grade.
Genmin said in terms of mine planning, the DID would be extracted first as it occurs near surface at the top of Baniaka’s geological profile.
The project’s current indicated and inferred DID mineral resource inventory sits at 63 million tonnes.
Soft oxide results
Soft oxide is much finer than DID with more material reporting to a size fraction of less than 1 millimetre.
Consequently, lump and fine yields are lower, as are lump and fine iron grades, which came in from Bond’s testwork at 63.3% and 64.3% respectively.
Iron product grades for lump and fines from the two soft oxide samples were 62.3% and 65.4%, at mass yields of 30% to 45%.
Genmin managing director Joe Ariti was pleased with progress from the pilot-scale tests.
“These initial high-grade results are outstanding for lump and fines products from near surface DID and immediately underlying soft oxide mineralisation,” he said.
“It gives us a competitive positioning against Africa’s iron ore producers and the value-in-testing work will provide initial exposure of our products to the Chinese market.”