Mamba Exploration completes drilling of gravity anomaly at Hyden rare earths project
St George holds hope for the projects which lie in an area that has delivered significant lithium results for other explorers.
Perth-based junior Mamba Exploration (ASX: M24) has completed an initial 58-hole drilling program at the Hyden rare earth elements (REE) project to test a gravity anomaly identified in a recent geophysical survey.
The area drilled totalled 2,500 metres and was approximately 2km to the east of recently discovered wide and shallow clay-hosted REE mineralisation.
Drill samples are currently being tested using portable x-ray fluorescence (pXRF) units to assist in classifying the rock units and determining the next steps for exploration.
As the units only detect two of the REEs, Mamba said full “wet chemical” analysis will be needed to accurately report REE concentrations in the samples.
Samples have been submitted to an ALS laboratory, with assays expected within six weeks.
March survey
The bedrock gravity anomaly was highlighted in a detailed ground gravity survey completed in March.
It comprised 419 stations on eight east-to-west lines and two north-to-south lines over the main area of interest.
Data highlighted a greenstone belt with a series of granite bodies to the east and west of the target, consistent with geological mapping and regional aerial magnetic interpretation of the area.
Modelling showed significant magnetic alteration and disruption along with a relative density low believed to be not consistent with the granite signature to the east and west.
A gravity anomaly appeared to post-date a series of late-stage Proterozoic dykes visible in the magnetic data, suggesting that the anomaly is a late-stage intrusive body and interpreted to represent a bedrock REE target.
Bedrock mineralisation
Mamba managing director Mike Dunbar said the company’s modelling of the target indicates it could represent bedrock REE mineralisation.
“The 3D inversion modelling has identified an area which appears to be a late-stage intrusion which crosscuts the greenstone belt that runs north-south through the eastern portion of the target area,” he said.
“It is encouraging that historical data, while limited, has identified that parts of the intrusion contain significant phosphates and rare earth oxides, supporting our view that we have identified a bedrock REE target here at Hyden.”