- Botswana Diamonds [LON:BOD] was the sector's biggest riser after it received the final Alrosa geological report on the exploration work undertaken on prospecting licence PL/117 in the Orapa area of Botswana.

Botswana Diamonds says the report identified four previously unknown mineralogical anomalies and significantly two are coincident with geophysical anomalies reported on 08 August 2014. Other highlights:

- Target AN117/2, with strong mineralogical and geophysical anomalies, located in the northern part of the licence, will be drilled in September. Hole 1 will target the south eastern part of the anomaly, which shows maximum amplitude on the magnetics. The second hole will be drilled in the centre of the anomaly.

- Target AN117/1 in the northwest has a very strong mineralogical signature. It will be drilled in September after further geophysical work to pinpoint drill-hole sites.

- Two further anomalies, C&D are thought to be kimberlite dykes or veinlets and will not be drilled at this time.

- Analysis of material on Prospecting Licence, PL/206, suggests that primary sources of diamonds can exist on the block. Further ground work will be done in Q4 2014.

Chairman John Teeling said: "The detailed mineralogical report received from Alrosa highlights targets on licence PL117 in Orapa. Four anomalies were identified, two of which also have strong geophysical signatures.

"We have identified the drill sites for two holes on anomaly AN117/2 which has very strong geophysical and kimberlite indicator mineral results.

"The second target, AN117/1, has very good mineralogical signatures. A little more work will be done in September to pinpoint the best drill location on AN117/1.

"It is significant that the evaluation strongly suggests that the chrome diopsides and diamonds recovered earlier are not all from the AK10 kimberlite known on PL117."

* * *

Coalfield Resources' [LON:CRES] net assets per share rose to 9.6p at the end of June - up from 9.1p at the end of the 2013.

The company's only significant investment is a 24.9% stake in Harworth Estates Property Group Limited in which it takes an active investment management role.

Net assets at the end of of June totalled £58.4m (FY13: £55.2m).

The group reports a profit from continuing operations before tax in the period of £3.2m (HY13 loss of £0.1m, FY13 profit of £3.3m) principally from its investment in Harworth Estates.

Chairman Jonson Cox said: "Our objective is to deliver value from our investment in Harworth Estates as it implements its strategy to maximise value across its portfolio. The first half of 2014, saw this strategy continue to deliver, generating a profit, and asset value growth, of £3.1m for CfR.

"Although we are only at an early stage in the process, we strongly believe the Harworth Estates team has laid the foundations for continued value realization. When it is equipped with an improved capital structure, we believe further value can be realised both from the portfolio through organic growth and by adding value through selective brownfield property development and acquisition opportunities.

"We look forward to working alongside the Pension Protection Fund, our new co-shareholder of Harworth Estates, to optimise the model for the business and drive growth for the benefit of all shareholders."

* * *

Griffin Mining [LON:GFM] has confirmed that the planned upgrade of the processing facilities at the Caijiaying mine are proceeding on time and within budget.

According to the schedule, the processing of ore from the mine has now been suspended for a period of two months to enable new crushing and milling equipment to be installed and integrated into the existing processing facilities.

Mining and haulage of ore will continue during this period and be stockpiled to be processed upon the commissioning of the expanded processing facilities.

With the doubling of processing capacity at Caijiaying, it is expected that the stockpiled ore will be processed by year end resulting in annual production of zinc metal in concentrate to be in line with 2013 results.

Administrative state issues in China outside Griffin's control continue to delay the grant of a new mining licence over the unmined Zone II and ancillary areas at Caijiaying. It is expected to be issued later this year.

* * *

Antofagasta [LON:ANTO] has announced that Nelson Pizarro will be leaving its Board after being appointed as the chief executive officer of Corporacion Nacional del Cobre de Chile (Codelco).

The changes take effect at the beginning of next month. Pizarro has been a non-executive director of Antofagasta since 2012.

* * *

Herencia Resources [LON:HER] says it has been advised that environmental approval required to undertake a drilling programme at its 70%-owned and managed Paguanta zinc-silver project in Chile has been granted.

The company says this is a critical step in the progression of the development of the Patricia project as it not only provides the necessary approval to potentially expand the Patricia resource but importantly can assist in the process for the approval of the final project EIS.

Managing director Graeme Sloan said: "Whilst Picachos remains our focus, we are mindful of all the good work that continues to be carried out at Paguanta to progress the project toward production.

"The approval of our drilling EIS is another important step in the full project EIS approval, given much of the datacollected, and the process followed, has enhanced our understanding of the protocols necessary for project approval..

"It is worth remembering that Paguanta is not a project located in the depths of Africa, but rather a relatively low capex project, with excellent grades, perfectly located in a first-world country.

"The emerging potential at Paguanta East, whilst early days, is now another 'leg' to the exciting Herencia story and we will certainly look to maximise the opportunities that may arise from its porphyry-copper potential.

"In closing, market watchers may have noted the recent positive gains in the zinc price. We at Herencia are strongly of the belief that these zinc price rises, along with the fall in global stockpile inventories, will continue as major zinc mines continue to shut down. In this setting, we will maintain the forward progress at Paguanta, while looking at ways to keep start-up capital costs at a minimum and positioning the project to rapidly move into production to take advantage of a strengthening zinc-silver price."

At 4:08pm:

[LON:AMI] African Minerals Ltd share price was -0.25p at 33.5p

[LON:ANTO] Antofagasta PLC share price was -15.75p at 805.75p

[LON:AQP] Aquarius Platinum Ltd share price was +0.38p at 24.13p

[LON:BEM] Beowulf Mining PLC share price was +0.12p at 3.62p

[LON:BKY] Berkeley Resources Ltd share price was 0p at 16.5p

[LON:BOD] Botswana Diamonds PLC share price was +0.51p at 3.13p

[LON:CEY] Centamin PLC share price was -0.22p at 74.78p

[LON:CHL] Churchill Mining PLC share price was 0p at 22.75p

[LON:CRES] Coalfield Resources share price was +0.28p at 6.33p

[LON:CZA] Coal of Africa Ltd share price was -0.2p at 2.91p

[LON:FDI] Firestone Diamonds PLC share price was -0.5p at 37.75p

[LON:FRES] Fresnillo PLC share price was -2.5p at 1028.5p

[LON:GEMD] Gem Diamonds Ltd share price was -2.87p at 195.13p

[LON:GFM] Griffin Mining share price was +0.01p at 37.63p

[LON:HER] Herencia Resources PLC share price was -0.01p at 0.42p

[LON:HOC] Hochschild Mining PLC share price was +0.1p at 167.1p

[LON:KMR] Kenmare Resources PLC share price was -0.62p at 13.13p

[LON:VED] Vedanta Resources PLC share price was -6p at 1033p

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