Uranium developer Deep Yellow (ASX: DYL) has unveiled a new mineral resource estimate for its Omahola project in Namibia, comprising the Inca, MS7 and Ongolo deposits.
Previous exploration from 2009 to 2013 established a measured, indicated and inferred resource base at the project of 45 million pounds at 420 parts per million uranium oxide, with a 250ppm cut-off.
The new and upgraded estimate sits at 125.3Mlb at 190ppm uranium oxide with a 100ppm cut-off across the measured, inferred and indicated categories.
At a 150ppm cut-off, the deposits contain a combined 82.9Mlb at 269ppm uranium oxide.
Omahola provides Deep Yellow with another exploration target in the Tumas paleochannel due to the significant accumulation of uranium and the partially-drilled nature of the extensive prospective target zone extensions which remain underexplored and have potential for resource expansion.
Its location is believed to demonstrate similar characteristics to Paladin Energy’s (ASX: PDN) nearby Langer-Heinrich mine with reserves of 84.8Mt at 448ppm uranium oxide.
Deep Yellow has started work on a shallow 7,100m, 200-hole reverse circulation drilling program to unlock further value from Omahola’s basement targets.
Alaskite Alley location
Omahola occurs within the highly-prospective Alaskite Alley corridor which is host to major uranium deposits including Rössing, Husab, Etango and Valencia.
These deposits contain more than 800Mlb uranium oxide, with Rössing alone having produced in excess of 200Mlb.
Omahola occupies acreage across the northwest-southeast trending zone within the corridor and mineralisation occurs across Inca, MS7 and Ongolo.
The Inca deposit contains a unique type of skarn-hosted uranium mineralisation occurring within an iron-rich metasomatized mafic gneiss sequence above a thick marble layer.
It is hosted within a biotite-rich fels, amphibole gneiss and skarn package, which includes near monomineralic garnet, iron-titanium oxide, clinopyroxene and scapolitite rich rocks.
MS7 is an alaskite-type mineralisation, with uranium hosted by leucogranite dykes crosscutting pyroxene-hornblende gneiss of the Khan Formation above a contact with thick marble.
Mineralisation at Ongolo is mostly confined to cross-cutting pegmatitic leucogranite sheets or dykes.
There is also a lithological control evident on ore distribution as most of the ore occurs in dykes which intrude pyrite and pyrrhotite-rich gneisses and skarn rocks immediately below the prominent marble layer.