12 June 2015

Positive drilling results at Souma

Avocet Mining PLC ("Avocet" or "the Company") announces positive results from its drilling campaign at Souma, Burkina Faso. These are the first results from an ongoing drilling and metallurgical test work programme that commenced in April 2015. The programme will determine to what extent Souma might provide satellite ore feed to Inata, with minimal capital cost, or would be best suited to a low cost standalone heap leach operation, benefiting from synergies with Inata.
Previous drilling has indicated that mineralisation at Souma is quartz hosted, and does not have the same carbonaceous ore types as seen at Inata. The objectives of the programme are to confirm that Souma's metallurgy is oxide and non-carbonaceous, and to upgrade the existing resource of 0.68 million ounces in order to generate a maiden ore reserve.
Highlights of this programme are set out below:

DYNAMITE

 DYRC0215: 18m @ 4.33 g/t Au from 20m

 DYRC0208: 8m @ 7.70 g/t Au from 25m

 DYRC0221: 22m @ 2.28 g/t Au from 2m

 DYRC0221: 8m @ 5.36 g/t Au from 16m

 DYRC0158: 3m @ 12.48 g/t Au from 27m

 DYRC0167: 7m @ 3.68 g/t Au from 14 to 21m

 DYRC0167: 14m @ 2.62 g/t Au from 43m

 DYRC0184: 6m @ 4.74 g/t Au from 44m

 DYRC0184: 3m @ 6.12 g/t Au from 27 to 30m

 DYRC0217: 7m @ 3.99 g/t Au from 9m

 DYRC0205: 15m @ 1.83 g/t Au from 6m

 DYRC0202: 12m @ 2.21 g/t Au from 45m

 DYRC0167: 7m @ 3.68 g/t Au from 14m

 DYRC0206: 15m @ 1.63 g/t Au from 30m

 DYRC0201: 14m @ 1.74 g/t Au from 2m

 DYRC0200: 4m @ 5.90 g/t Au from 37m

 DYRC0223: 7m @ 3.33 g/t Au from 39m

 DYRC0233: 19m @ 1.03 g/t Au from 0m

 DYRC0225: 5m @ 3.87 g/t Au from 8m

 DYRC0184: 3m @ 6.12 g/t Au from 27m

 DYRC0155: 4m @ 4.52 g/t Au from 41m

 DYRC0235: 13m @ 1.38 g/t Au from 1m

 DYRC0154: 7m @ 2.03 g/t Au from 30m

 DYRC0199: 11m @ 1.26 g/t Au from 19m

 DYRC0226: 9m @ 1.32 g/t Au from 32m

 DYRC0223: 7m @ 1.65 g/t Au from 15m

 DYRC0163: 10m @ 1.06 g/t Au from 5m

 DYRC0227: 10m @ 1.01 g/t Au from 26m

The above intercepts were determined using a 0.5g/t cut off, top cut 20g/t, minimum width to accumulate 2metres, maximum waste 2metres.

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These encouraging results are from an area towards the north of the Souma trend known as Dynamite, as shown in the figure below, and are expected to contribute to the programme's objectives of increasing confidence in the existing orebody (as set out in the Appendix) and growing the resources.
A total of 63 reverse circulation ("RC") holes for a total of 2,921 metres have been drilled at Dynamite. The Dynamite drilling programme reduces the drill spacing to 12.5m x 10m, as mineralisation at Dynamite is hosted within a complex intersecting array of shears and requires close spaced drilling. As well as infilling previous drilling, additional holes were drilled at Dynamite that targeted a northeast cross-cutting trend with potential for extension of the zone. The drill holes are designed to test only the weathered portion of the deposit that may

be amenable to heap leach processing.

Souma

Souma North

Inata

N'Darga

Dynamite

Miilam North

Miilam Central

Mormosol

Miilam South

Bélahouro exploration licences - gold in auger samples on a background of VTEM response, showing the cluster of auger anomalies associated with the Inata mine and the prominent anomalies associated with the Souma trend, approximately 20 kilometres east of Inata. Avocet owns 100% of the Souma licence, which extends until 2017.

The full programme of RC drilling is expected to be complete in July. The results of the remaining RC drilling will be announced when they become available, covering Miilam and other areas within the Souma trend. A total of 20 diamond drilling ("DD") holes for a total of
882 metres have been completed for metallurgical test work at Miilam Central and Dynamite, which are the main deposits. Samples from these areas have been sent for test work, which is expected to take several months. DD holes remain to be drilled in other areas for metallurgical test work purposes.
The information in this release that relates to the exploration results is based on information supplied by Mr Robert Seed, a competent person. Robert Seed is employed by Avocet Mining

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and has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he is undertaking to qualify as a Competent Person as defined in the 2012 Edition of the "Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves". Robert Seed consents to the inclusion in the release of the matters based on his information in the form and context in which it appears.

FOR FURTHER INFORMATION PLEASE CONTACT

NOTES TO EDITORS

Avocet Mining PLC ("Avocet" or the "Company") is an unhedged gold mining and exploration company listed on the London Stock Exchange (ticker: AVM.L) and the Oslo Børs (ticker: AVM.OL). The Company's principal activities are gold mining and exploration in West Africa.

In Burkina Faso the Company owns 90% of the Inata Gold Mine. The Inata Gold Mine poured its first gold in December 2009 and produced 86,037 ounces of gold in 2014. Other assets in Burkina Faso include eight exploration permits surrounding the Inata Gold Mine in the broader Bélahouro region. The most advanced of these projects is Souma, some 20 kilometres from the Inata Gold Mine.

In Guinea, Avocet owns 100% of the Tri-K Project in the north east of the country. Drilling to date has outlined a Mineral Resource of 3.0 million ounces, and in October 2013 the Company announced a maiden Ore Reserve on the oxide portion of the orebody, which is suitable for heap leaching, of 0.5 million ounces. As an alternative, the potential exists to exploit the entire 3.0 million ounce Tri-K orebody via the CIL processing method. The Company announced on 2 April 2015 that an exploitation permit had been awarded for Tri-K.

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Appendix

Information on the Souma trend

The Souma Trend is part of a larger 30 kilometre long and 3 kilometre wide structural zone that separates a major granitic batholith in the east from the volcano-sedimentary terrain in the west. Previous drilling has defined a resource of 675,600 ounces, of which 74% is Inferred and will benefit from the ongoing infill drilling programme.

The table below sets out the current Souma Mineral Resources (using a cut-off of Au >0.8g/t). Category Tonnes Grade Au (g/t) Metal
(ozs)

Measured - - - Indicated 2,410,000 2.32 179,500
Meas+Ind 2,410,000 2.32 179,500

Inferred 9,220,000 1.67 496,100
Meas+Ind+Inf 11,630,000 1.81 675,600
The current drilling programme is designed to upgrade areas of Inferred resources, increase oxide resources and provide metallurgical data required for a feasibility study. The average drill hole depth is 50 metres with the deepest hole being 100 metres. All holes are angled at 60 degrees towards the east. Samples have been submitted for gold analysis by fire assay using a
50 gramme charge at the SGS laboratory in Ouagadougou and the Intertek laboratory in
Ghana. Avocet has implemented industry standard QAQC procedures. The program includes diamond drilling to generate material for metallurgical test work.

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