Meeka Gold has revealed total rare earth oxides up to 633 parts per million in leached and oxidised surface horizon auger samples at its Cascade project near Esperance in WA. Total rare earth oxides above 400 parts per million were present across multiple samples within a 250 square km area and Meeka speculates that the large cerium anomalies point to possible deeper rare earths enrichment.
The auger samples reported by Meeka were collected between 2010 and 2012 during gold exploration and the company has assayed the samples for rare earths for the first time. Meeka claims to be the first explorer considering the project area for rare earth elements.
Auger samples were taken from a depth of 1 metre in what Meeka describes as the depleted surface zone. The samples were from the central area of the Cascade project.
Meeka also revealed strong cerium anomalies at surface that it believes might be the potentially less mobile mineral cerianite. The company said cerium surface anomalism is a common marker observed above deeper accumulations of rare earths mineralisation in regolith hosted deposits.
Regolith hosted rare earths originate through weathering of underlying felsic rocks such as granite and gneiss. The company is confident the underlying geology is a good source of rare earths and the process of mobilisation and subsequent accumulation within the regolith horizon has occurred at Cascade.
Regolith-hosted rare earth element deposits are also known as ion-adsorption deposits because the rare earths physically adhere to the clay particles. As a result, between 60 and 90 per cent of the rare earth elements can be recovered and extracted by ion-exchange leaching with dilute electrolyte. Ore zones are generally 5-20m thick and low grade, 0.04-0.3 per cent rare earths. Mining and processing costs are low giving rise to economic production.
Previous aircore drilling and rare earths sampling covering the southern half of the Cascade tenements was also successful and the company now considers that “the Cascade rare earths project has the potential to host significant accumulations in the shallow regolith.”
Meeka plans to get busy with the drill bit at Cascade in the second half of the year, targeting the clay horizon below the large cerium anomalies and high-grade rare earths samples.
Meeka’s Cascade project covers 2,068 square km and places the company at the centre of regolith hosted rare earths exploration in a region that is rapidly emerging as a highly prospective ionic clay type rare earths province.
The company’s flagship Murchison project contains a 1.1-million-ounce gold resource. The regional scale Cascade and Circle Valley rare earths projects are adding diversification potential for Meeka at a time of global rare earths supply shortage and interest.
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By Matt Birney
