Cypress Confirms Leach Results for Clayton Valley Lithium Project in Nevada - Seite 3

Further tests are ongoing with the following goals: 1) refining the leach conditions, 2) checking for mineralogical variability from hole to hole, and 3) determining effective means of recovering the lithium from the leach solutions. In December, samples were sent to a second independent laboratory, Continental Metallurgical Services, in Butte, Montana. The two samples were composites of oxidized and reduced intervals from hole DCH-02. A one-hour leach of these samples, using 10% sulfuric acid at 10% solids and 50°C, returned lithium extractions of 62% and 65%, respectively. These results, if plotted on the extraction curve from hole DCH-05, plot somewhat higher, possibly indicating differences do exist in mineralogy from hole to hole, or other differences in laboratory conditions, such as intensity of agitation during leaching. The results are consistent, however, with the observation that the lithium in the subsurface claystone can be leached with high levels of extraction in sulfuric acid.  

Summary of Leach Tests
Test	Sample	Head Assay	Temp	Extraction (%)
ID	Type	ppm Li	oC	Li
OL-02	Oxidized	860	room	39
RL-02	Reduced	1100	room	55
OL-06	Oxidized	860	80o	74
RL-06	Reduced	1100	80o	74
OL-07	Oxidized	860	50o	67
RL-11	Reduced	1100	50o	80
Li-A2	Oxidized	1020	50o	62
Li-A1	Reduced	972	50o	65

Samples were ground to minus-10 mesh and leached with a solution of 5% sulfuric acid for 4 hours at 10% solids. OL and RL series samples were core from DCH-05, tested at SGS and leached for 4 hours. Samples Li-A1 and Li-A2 were core from DCH-02, tested at Continental Metallurgical Services, and leached for 1 hour. In all tests, the leach solution was monitored but no additional sulfuric acid was required to maintain an acidic pH. The mixture was then filtered and rinsed with residue and solutions submitted for assay.