|The Thambani exploration licence, located in the Mwanza District, was originally granted by the Malawi Minister of Natural Resources, Energy and Environment on September 10, 2010 in respect of an area of 468km2. In September 2013 and September 2015, the Government of Malawi granted further two year renewals for the licence. At the second renewal the Company requested a reduction in the licence size to the current area of 136.9km2.|
Mkango's exploration activities to date include acquisition of Landsat7 and ASTER satellite imagery for the licence area, systematic ground radiometric surveys to confirm and detail previously-known airborne anomalies, reconnaissance geological mapping and litho-geochemical sampling programs. The work has identified a number of potential uranium and associated Nb-Ta targets over the Thambani Massif, which is mainly composed of nepheline-bearing syenite gneiss, forming two prominent ridges known as Thambani East Ridge and West Ridge.
A systematic ground radiometric survey completed by Mkango previously revealed two distinct uranium anomalies occurring across the Thambani East and West Ridges: A strong uranium anomaly, measuring approximately 3km by 1.5km, occurs along the length of the Thambani East ridge, with a north-south trend, and a second uranium anomaly, measuring approximately 1.5km by 0.4km, occurring on the West Ridge along the western contact of the nepheline-bearing syenite body with the biotite-hornblende gneisses.
Mkango completed a trenching program across the Thambani Massif primarily focused on two sites of historical uranium exploration, known as the Chikoleka and Little Ngona targets. An initial set of 9 trenches, selected on the basis of anomalous ground radiometric results, have been re-examined and geochemically sampled across profiles from soil/overburden into bedrock.
The first set of assay results of 142 soil and rock chip samples returned variably anomalous U, Nb and Ta values in most trenches, ranging up to 4.70 per cent. U308, 3.25 per cent. Nb2O5 in soil and up to 0.42 per cent. U308, 0.78 per cent. Nb2O5 and 972 ppm Ta2O5 in rock chips, notably higher than results from the 2013 reconnaissance surface geochemical sampling program. Results associated with the 10 best U308 assays are summarized in Table 1.
Preliminary mineralogical studies carried out on six rock samples from the Little Ngona River and Chikoleka targets, using SEM at the Natural History Museum London, indicate that pyrochlore group minerals, mainly betafite, are the principal carriers of U, Nb and Ta for these samples.
Assays from the 10 highest - U308 samples from the Thambani trenching program
|Results of Airborne Radiometric Survey|
Results of Airborne Magnetic Survey