LONDON (Alliance News) - Alexander Mining PLC on Thursday reported disappointing results from a recent joint venture testing heap leaching.
Alexander had been working with lead technology consultant Nicholas Welham on a one-off proof of concept and tested four different lithium minerals: spodumene, petalite, lepidolite, and zinnwaldite.
Leaching of lithium was achieved with all four at ambient temperature and pressure.
However, Alexander said, the rates of dissolution of the lithium were too low, and only zinnwaldite appears to have any promise for heap leaching.
"No further work is planned at this stage. However, the company retains a keen interest in the lithium mining and processing sector given its importance to the revolution in electric vehicles and transportation currently well underway," said Alexander.
"With growing evidence regarding the operational and economic difficulties with brine type lithium extraction methods, such as increased capital intensiveness, extended time to production, production volume variances from evaporation rates, the processing of lithium from hard rock resources has become a point of focus."
"Accordingly, the use of heap leaching as a possible processing method for the low-cost extraction of lithium remains of interest to Alexander and it will continue to seek opportunities to use its expertise in this area," the firm continued.
Shares were 15% lower on Thursday at a price of 0.058 pence each.
