Sydney, Jan 31, 2017 AEST (ABN Newswire) - Global Geoscience Limited (ASX:GSC) is pleased to provide the company's Quarterly Activities Report for the period ended 31 December, 2016.

Highlights

- 1st stage metallurgical testwork results support potential for simple, low-cost processing using established technologies to produce lithium carbonate and boric acid

- Recognition of Searlesite Zone hosting high-grade Li-B Resource at South Basin

- Maiden drill program completed with two holes at North Basin and three holes at South Basin - results pending

- Ongoing metallurgical testwork focussing on producing a Li-B rich searlesite concentrate to enhance the low-cost acid leach processing route

Exploration Activities

Rhyolite Ridge Lithium-Boron Project, Nevada

Rhyolite Ridge is a lithium-boron deposit located in southern Nevada, close to existing infrastructure. The project lies 25km west of Albermarle's Silver Peak lithium mine and is 340km by paved road from the Tesla Gigafactory near Reno. Rhyolite Ridge is one of the largest lithium and boron deposits in North America and has the potential to become a strategic, long-life and low-cost source of lithium and boron. Global Geoscience has the exclusive right to purchase 100% interest in the project with no royalties or residual interests.

Mineralisation is hosted by sedimentary rocks, representing a potential third source of lithium - in addition to brine and pegmatite types. The mineralised sedimentary rocks are thick, shallow and flat lying, making them ideally suited to open pit mining methods. The deposit has potential for simple, low-cost processing to produce lithium carbonate and boric acid. The relatively simple process route, involving crushing, screening, flotation and dilute acid leaching, is expected to compare favourably to other sources of lithium including brine and spodumene deposits. The key to the simple processing route is the presence of the mineral searlesite, an acid-leachable sodium borosilicate, that is associated with both lithium and boron mineralisation.

The project consists of two sedimentary basins (North and South) located four kilometres apart. South Basin contains a Resource of 3.4 million tonnes of lithium carbonate and 11.3 million tonnes of boric acid. The Resource is open in three directions and is likely to increase in size with additional drilling. North Basin contains significant lithium-boron mineralisation intersected in wide-spaced historic drilling (1980's), but no resource has been estimated to date.

The South Basin Resource contains a high-grade Li-B zone of 65Mt at 1.0% Li2CO3 (1910 ppm Li) and 9.1% H3BO3 (1.6% B) for a total of 650,000 tonnes of lithium carbonate and 5.9 million tonnes of boric acid. This mineralisation is rich in the mineral searlesite and has been termed the Searlesite Zone.

Metallurgical Testwork

The metallurgical program is evaluating a simple process route involving crushing, screening and flotation followed by dilute-acid leaching to extract lithium and boron to produce lithium carbonate and boric acid. Key findings from the testwork completed to date are:

- Li and B are contained in acid soluble minerals including searlesite and can be leached using dilute sulphuric acid (20%) with high recoveries.

- Li-B rich mineralisation occurs in a relatively coarse-grained sedimentary rock where the dominant mineral (>40% by weight) is searlesite, a sodium borosilicate mineral.

- Acid consuming carbonate minerals (calcite and dolomite) are also present as coarse grains, meaning they are amenable to removal by flotation prior to acid leaching.

- A searlesite concentrate with low carbonate content is expected to translate to significantly lower acid consumption.

For further information regarding metallurgical testwork, refer to the following reports that are available to view on the Global Geoscience website:

"Discovery of Searlesite Zone Enhances Potential for Low-Cost Processing" dated 16/11/2016
(http://www.abnnewswire.net/lnk/562JAR99)

"Metallurgy and Drilling Update Nevada Lithium-Boron Project" dated 23/01/2017
(http://www.abnnewswire.net/lnk/I60R58JP)

High-Grade Searlesite Mineralisation

Recent work led to the recognition the high-grade searlesite-rich zone at South Basin. The searlesite mineralisation is the highest value mineralisation within the South Basin Resource and constitutes 97% of the high-grade component. It occurs in the Upper Lens of the deposit. The Searlesite Zone:

- Has an average grade of 1.0% Li2CO3 (1910 ppm Li) and 9.1% H3BO3 (1.6% B)

- Averages 20 metres thickness over an area of approximately 1x1.8km

- Is shallow and outcrops along the western margin of South Basin

- Is open in three directions and likely to increase in size with step-out drilling

Drilling Program

The maiden drilling program commenced in December 2016 and was completed by mid-January. Two holes drilled at North Basin tested Li-B mineralisation previously indentified and drilled by US Borax in the 1980's. Three holes drilled at South Basin tested for extensions to the high-grade Li-B searlesite mineralisation. All drill holes are outside the current Resource area. Assay results are expected over the next 2 to 3 weeks. Core samples from the North Basin have been added to the metallurgical program to ensure all types of mineralisation are tested.

For further information regarding the drilling program, refer to the following reports that are available to view on the Global Geoscience website:

"Drilling Commences at Nevada Lithium-Boron Project" dated 12/12/2016
(http://www.abnnewswire.net/lnk/37W9LJJ5)

"Metallurgy and Drilling Update Nevada Lithium-Boron Project" dated 23/01/2017
(http://www.abnnewswire.net/lnk/9X5K87BF)

March Quarter Work Program

The March quarter work program will continue to focus on metallurgical testwork. Core obtained from recent drilling at North Basin will be included in the testwork. Assay results will be received for the recently completed drilling program and, subject to results, a resource estimate will be completed for the North Basin.

With the completion of the initial metallurgical testwork, the Company aims to make a decision during the March quarter regarding commencement of a pre-feasibility study.

Other Projects in the USA

The Company holds several other projects in Nevada (Tokop, Lone Mt and Bartlett) and Arizona (Towers Mt and New Morenci). No exploration work was undertaken on these projects during the December quarter and none is planned for the current quarter.

To view the quarterly report, please visit:
http://abnnewswire.net/lnk/4LICG8E6


About Global Geoscience Limited

Global Geoscience Limited ASX GSCGlobal Geoscience Limited (ASX:GSC) is a Sydney-based mineral exploration company specialising in greenfield exploration and mineral discovery. The Company's main focus is for copper, gold and silver on its mostly 100%-owned projects in Nevada and Arizona in the United States, and Peru in South America.

 


Contact

Bernard Rowe
Managing Director
Global Geoscience Ltd
T: +61-2-9922-5800
M: +61-4-1944-7280
Email: browe@globalgeo.com.au



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