- Tri-Star Resources [LON:TSTR] said engineering design, procurement of long-lead-time items and plant layout for the Oman Antimony Roaster (OAR) continues to advance.

The OAR is being constructed by the company's Omani joint venture company, Strategic & Precious Metals Processing LLC (SPMP). Tri-Star has a 40% equity interest in SPMP.

SPMP has been pleased with responses from potential suppliers of feedstock and has been conducting bulk commercial trials with concentrates containing both antimony and gold. Further trials and test-work are ongoing.

Additional resources have been added by SPMP to the project team and Tri-Star is confident that the OAR remains on course for commissioning by the end of 2017, as previously advised.

The company is also pleased to report that over half of the capital outlay has been bid committed or incurred by SPMP. Site construction activity in Sohar has now commenced and major capital items are scheduled to arrive on site during the first half of 2017.

* * *

Revenues from a Singapore auction of rough ruby extracted by Gemfields' [LON:GEM] 75%-owned Montepuez Ruby Mining in Mozambique raised $30.4m - the fourth highest ruby auction result to date.

The average realised price was $27.79 per carat and 1,094,406 carats were sold (80% by weight or 85% by market value) out of the total of 1,372,145 carats offered.

Gemfields says seven Montepuez auctions have been held since June 2014 generating $225.7 million in aggregate revenues.

Chief executive Ian Harebottle said: "We are very pleased with the results of Gemfields' seventh Montepuez ruby auction despite some of our customers being unable to attend while they adjust to the regional demonetisation policy changes they've experienced over the past few weeks.

"The prices achieved at this auction, combined with the high percentage of the value sold, fully support our view of ongoing solid demand for responsibly sourced Mozambican rubies across key markets and categories. The recent prices obtained for fine cut-and-polished Mozambican rubies by international auction houses further underscore the exciting trajectory for rubies from Mozambique.

"As always, we thank our customers, our business partners, our host government and give credit to every member of our devoted and hard-working global team."

* * *

Rambler Metals & Mining [LON:RMM] has posted a Q1 2017 stub pre-tax loss of $2.5m. In Q1 2016 it posted a $421,000 pretax profit.

"For the second consecutive quarter, the operation delivered at a higher planned tonnage and continues to focus on accelerating the Phase II mine development," said president and CEO Norman Williams.

"During the next two to three quarters we envisage a steady increase in production rates targeting our first expansion milestone of 1,250 metric tonnes per day from the mine by mid calendar 2017.

"Through this LFZ development we will enable the mine to continuously deliver at these higher targeted rates by incorporating much larger stoping blocks into the production plan.

"Further engineering and evaluation of two very exciting opportunities around shaft rehabilitation and ore pre-concentration continued during the period.

"Through the integration of these additional opportunities the next stage of expansion, Phase III, will aim to further reduce the project's unit cost in line with the top quartile of the worlds copper producers. We will continue to provide an update on these projects as they progress."


- Continuing to implement mine development into the Lower Footwall Zone ('LFZ') and project optimization for the Phase II expansion with a new projected mine life of over 21 years;

- Production of 69,609 dry metric tonnes ('dmt') of ore, in line with the previous quarter; Copper grades of 1.7% and gold grades of 1.1 g/t; Milling recoveries for copper and gold averaged 96.5% and 65.9% respectively; Concentrate grade average of 26.4% copper with 12.6 g/t gold;

- Net cash direct costs per pound of saleable copper net of by-product credits ('C1') for the quarter were US$2.08 (Q4/16: US$1.71, Q1/16: US$1.62); The Company anticipates C1 costs will remain at or above these levels until it sustains its planned Phase II expansion throughput of 1,250 metric tonnes per day ('mtpd'). Once Phase II expansion throughput reaches 1,250 mtpd, on a sustainable basis, C1 costs are targeted to return to approximately US$1.70.

* * *

Tanzania-focused Kibo Mining [LON:KIBO] has awarded the engineering, procurement and construction contract for the proposed Mbeya coal to power project thermal power plant to SEPCO III.

A legally binding EPC cover agreement between Kibo's wholly owned subsidiary Mbeya Power Ltd and SEPCO III was signed today. The agreement incorporates the complete EPC-contract as well as the EPC co-ordination agreement, the latter governing the implementation and execution of the EPC contract, as well as the OEM contract submitted by General Electric and which constitutes an integral part of the EPC contract.

The full EPC contract will remain subject to potential change, pending finalisation of the power purchase agreement and final requirements by lenders and equity investors during financial close. These changes will however only relate to changes required as a result of specific requirements in the PPA or final MCPP-funding arrangements.

Chief executive Louis Coetzee said: "We are extremely pleased to award the EPC contract to SEPCO III and to do so within the time schedule previously announced. Over the past two months the SEPCO III bid has been the subject of intense scrutiny, clarification and negotiation and has passed all tests with flying colours.

"We are particularly pleased with the high standard of professionalism, depth of knowledge and experience, capacity and capability that has been demonstrated by SEPCO III in this process. In SEPCO III we not only have a highly capable EPC contractor but also a loyal and true partner on whose support we can invariably rely on for the further development of the MCPP.

"Signing the EPC cover Agreement is the most decisive step forward to date in the development process of the MCPP and a true watershed moment in the history of the MCPP. The EPC price is one of the most, if not the most important, factors that determines the ultimate viability of a project like the MCPP. With certainty on the EPC price now we can confidently state that the MCPP is not only definitely viable, but also very robust and that it has exceeded all our expectations to date.

"The final EPC price will now also allow us to finalise the integrated financial model for the MCPP, but more importantly to finalise PPA negotiations expeditiously, as soon as the Tanzanian Government has concluded its final policy changes on the procurement of power projects like the MCPP. In this regard the Company continues to work closely with the Tanzanian Government and is expecting this process to be concluded very soon and with significantly positive outcomes for the energy sector in Tanzania."

* * *

Horizonte Minerals [LON:HZM] has announced the issuance of a request for proposals to engage consulting firms to prepare a definitive feasibility study for the company's 100% owned Araguaia nickel project which is being developed as the next major nickel project in Brazil.

The RFP follows from positive economic results of the new pre-feasibility study released in October and the successful fundraise of £9 million approved by shareholders on 30 November.

Araguaia is located south of the Carajas mining district in the State of Para in northern Brazil.

The tender process will close in January and successful groups will be announced and commence work in February.

Chief executive Jeremy Martin said: "The preparation for the Feasibility Study for Araguaia is another milestone for the Company, as we advance the Project towards construction. The selection of the Engineering group or EPCM group to undertake the feasibility study will be a key decision, we want to ensure that the study will allow a seamless progression into the implementation phase.

"It has been a busy year for Horizonte having delivered the robust economics for Araguaia in the PFS and work at the Project continues to progress according to schedule as we move into the final stages of the year and into the Feasibility stage. As we enter this exciting stage it is encouraging to see the nickel price increase with a number of positive reports in the market place continuing to point to robust fundamentals for the metal for 2017 and beyond.

"We are confident that the project milestones going forward are well aligned with nickel fundamentals. 2017 will be a very active year for the Company and we look forward to keeping the market updated with our progress."

At 4:05pm:

[LON:BEM] Beowulf Mining PLC share price was +0.01p at 5.38p

[LON:BKY] Berkeley Energia Ltd share price was +3.75p at 52.75p

[LON:CEY] Centamin PLC share price was +3.35p at 119.75p

[LON:CZA] Coal of Africa Ltd share price was +0.19p at 3.5p

[LON:FDI] Firestone Diamonds PLC share price was -0.5p at 51.75p

[LON:FRES] Fresnillo PLC share price was +9.5p at 1110.5p

[LON:GEM] Gemfields PLC share price was +1.01p at 55.88p

[LON:GEMD] Gem Diamonds Ltd share price was +1p at 107p

[LON:HOC] Hochschild Mining PLC share price was -6.25p at 197.35p

[LON:HZM] Horizonte Minerals PLC share price was -0.2p at 2.55p

[LON:KIBO] Kibo Mining share price was -0.25p at 6.75p

[LON:KMR] Kenmare Resources PLC share price was -8.5p at 241.5p

[LON:RMM] Rambler Metals and Mining PLC share price was 0p at 9.63p

[LON:TSTR] TriStar Resources PLC share price was +0.01p at 0.12p

[LON:VED] Vedanta Resources PLC share price was -17.5p at 903p

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