Last checked at 26 Nov 2009 07:00
Horizonte Minerals plc / Index: AIM / Epic: HZM / Sector: Mining
26 November 2009
Horizonte Minerals plc ('Horizonte' or 'the Company')
Lontra Project Update and Positive Metallurgical Test Results
Horizonte, the AIM quoted exploration and development company focused on Brazil and Peru, is pleased to announce positive metallurgical results from the laterite nickel discovery at its Lontra Project in the Carajas Mineral Province of Northern Brazil.
Overview:
Bottle role leach results at Lontra indicate suitability for low cost heap leach process
Significant nickel and cobalt recovery with low acid consumption in the limonite zone
Nickel recovery averaged 92% and cobalt 82% in the transition and silicate zones
Soil geochemical sampling completed to define additional targets
Drilling planned for Q1 2010 to define JORC compliant resource
Horizonte Chief Executive Jeremy Martin said, "These results indicate that the mineralogy of the Lontra deposit is amenable to tank or heap leaching at atmospheric pressure, with very good recoveries being obtained from the transition and silicate zones of mineralisation. Either of these technologies can be implemented at relatively low capital cost when compared to a pyrometallurgical route.
"Furthermore the results justify advancing the project to a resource definition drilling programme on the Northern and Raimundo targets initially tested in the first phase programme, as well as exploration drilling on the targets in the south and un-tested targets in the north. In addition the Company has recently completed a series of soil grids over a number of target areas, if these produce positive results it will potentially increase the overall tonnage potential of the Lontra Project."
Background to the Lontra Project
The Lontra Project is a greenfields discovery by Horizonte, situated in the Araguaia mobile belt, which flanks the eastern margin of the Carajas Mineral Province of northern Brazil. The project is located 80km south of the major lateritic nickel project operated by Xstrata plc at Serra da Tapa and Vale dos Sonhos (inferred resource of 73Mt at 1.5% Ni). It is also 7km northwest of the adjoining Vila Oito nickel project, where scoping studies have been carried out by Teck Resources Limited.
To date Horizonte has drilled 63 shallow diamond holes over an area of approximately 5km2. Due to the large size of the targets (approximately 1.5km2) this drilling is not yet of a sufficient density to be able to classify the mineralisation intersected into a resource category.
Metallurgic Samples
As a result of the positive first pass drilling results Horizonte prepared six samples from combined intervals of the diamond drill core samples for preliminary metallurgical bottle role leach tests. The samples were selected to represent the different mineralisation types mapped. The samples were processed and analyses carried out at the RPC - Process and Environmental Technology Laboratory in New Brunswick, Canada. The geochemical characteristics of the metallurgical samples are produced below.
| HOLE ID. | CODE | SAMPLE | FROM | TO | Ni | NiO | Co | Cu | Fe2O3 | MgO | SiO2 | Cr2O3 | MnO | Geoch |
| LON_DDH007 | 01 | DH_2648 | 8 | 8.7 | 1.78 | 2.26 | 0.097 | 0.23 | 61.2 | 2.27 | 11 | 0.34 | 0.67 | Limonite - Fe |
| LON_DDH007 | DH_2649 | 8.7 | 9.45 | 2.06 | 2.62 | 0.088 | 0.3 | 55.9 | 4.69 | 13.8 | 0.31 | 0.63 | Limonite - Fe | |
| LON_DDH007 | 02 | DH_2650 | 9.45 | 10.5 | 2.01 | 2.55 | 0.07 | 0.3 | 38.9 | 14.6 | 23.9 | 0.18 | 0.42 | Transition |
| LON_DDH007 | DH_2652 | 10.45 | 11.5 | 1.68 | 2.14 | 0.067 | 0.03 | 31.7 | 19.1 | 27.7 | 0.14 | 0.35 | Transition | |
| LON_DDH007 | DH_2653 | 11.45 | 12.5 | 1.70 | 2.16 | 0.071 | 0.017 | 30.7 | 21.3 | 29.3 | 0.17 | 0.35 | Transition | |
| LON_DDH007 | 03 | DH_2654 | 12.45 | 13.5 | 1.64 | 2.09 | 0.071 | 0.014 | 26.3 | 23 | 31.4 | 0.17 | 0.32 | Silicate |
| LON_DDH007 | DH_2655 | 13.45 | 14.5 | 1.69 | 2.15 | 0.065 | 0.026 | 26 | 23.5 | 32.3 | 0.18 | 0.28 | Silicate | |
| LON_DDH013 | 01 | DH_2762 | 6.7 | 7.7 | 1.59 | 2.02 | 0.14 | 0.14 | 38.8 | 3.72 | 17.5 | 0.31 | 0.48 | Limonite |
| LON_DDH013 | DH_2763 | 7.7 | 8.7 | 1.48 | 1.88 | 0.12 | 0.07 | 36.7 | 5.97 | 19.3 | 0.29 | 0.42 | Limonite | |
| LON_DDH026 | 01 | DH_3079 | 7.20 | 8.20 | 1.68 | 2.13 | 0.066 | 0.057 | 33.8 | 19.7 | 27.2 | 0.25 | 0.35 | Transition |
| LON_DDH026 | DH_3080 | 8.20 | 9.10 | 1.23 | 1.56 | 0.046 | < 0.01 | 29.8 | 21.1 | 31.2 | 0.19 | 0.34 | Transition | |
| LON_DDH026 | DH_3081 | 9.10 | 10.00 | 1.70 | 2.16 | 0.058 | < 0.01 | 31.8 | 18.8 | 27.8 | 0.28 | 0.33 | Transition | |
| LON_DDH026 | 02 | DH_3082 | 10.00 | 10.90 | 1.76 | 2.24 | 0.056 | < 0.01 | 28 | 21.6 | 30 | 0.22 | 0.3 | Silicate |
| LON_DDH026 | DH_3083 | 10.90 | 11.80 | 1.74 | 2.21 | 0.049 | < 0.01 | 26 | 22.4 | 32 | 0.22 | 0.28 | Silicate | |
| LON_DDH026 | DH_3084 | 11.80 | 12.70 | 1.72 | 2.19 | 0.057 | < 0.01 | 28.2 | 22.3 | 31 | 0.19 | 0.33 | Silicate |
Bottle Role Leach Tests
The table below shows the nickel and cobalt extractions, after 31 days, from 'bottle roll' leach tests on six 150g samples from diamond drill cores, samples were tested for a total of 90 days but optimal results were received after 31 days. Nickel extractions were between 89% to 99% for the transition and silicate mineralisation, calculated from liquid leachate analyses collected twice weekly. The leachate cobalt extractions were mostly in the range 70% to 80%. The acid consumption was between 226kg/t and 637kg/t for the samples. Lowest acid consumption was achieved in the surface limonite zone.
| Mineralisation Type | Sample | Recovery | Acid kg/t | ||
|
|
| Days | Ni % | Co % |
|
| Limonite | DDH007-01 | 31 | 565 | 55 | 216 |
|
| DDH013-01 | 31 | 68 | 76 | 203 |
| Transition | DDH007-02 | 31 | 89 | 82 | 534 |
|
| DDH026-01 | 31 | 91 | 82 | 453 |
| Silicate | DDH007-03 | 31 | 99 | 82 | 532 |
|
| DDH026-02 | 31 | 90 | 83 | 566 |
Follow up Field Programme
Following on from the successful first phase drill programme, geochemical soil lines have been extended east and west of the Northern and Raimundo targets, where recognisance geological work has indicated that additional targets may exist in these directions. Resource drilling will commence in Q1 2010 post the rainy season to bring the project up to JORC compliant resource.
The above information has been reviewed and verified by Mr. Jeremy Martin, a Director and Chief Executive of Horizonte, for the purposes of the Guidance Note for Mining, Oil and Gas Companies issued by the London Stock Exchange in March 2006. Mr. Martin, with seven years of mining and management experience, graduated with a degree in geology from the Camborne School of Mines, and an MSc in mineral exploration from the University of Leicester and is a member in good standing with the Society of Economic Geologists and the Institute of Mining Analysts.
With effect from 26 November 2009, the Company's nominated adviser changed its name from Hanson Westhouse Limited to Westhouse Securities Limited.
* * ENDS * *
For further information visit www.horizonteminerals.com or contact:
| Jeremy Martin | Horizonte Minerals plc | Tel: 020 7016 9132 |
| David Hall | Horizonte Minerals plc | Tel: 020 7016 9132 |
| Richard Baty | Westhouse Securities Limited | Tel: 020 7601 6100 |
| Martin Davison | Westhouse Securities Limited | Tel: 020 7601 6100 |
| Hugo de Salis | St Brides Media & Finance Ltd | Tel: 020 7236 1177 |
| Felicity Edwards | St Brides Media & Finance Ltd | Tel: 020 7236 1177 |
Notes:
Horizonte Minerals plc is an AIM quoted exploration and development company with a portfolio of gold, silver and base metal projects in producing mineral districts in Brazil and Peru. The Company is focused on creating value by generating and rapidly advancing new exploration projects to joint venture out to the major mining companies, providing mid-term cash flow which is then used to develop the business and pipeline projects.
Horizonte has four strategic partnerships: AngloGold Ashanti Limited ("AngloGold"), Troy Resources NL, LGA Mineração e Siderugia Ltda and Barrick Gold Corporation, which the Company is working together with to develop its multi commodity portfolio and explore further development opportunities in Brazil and Peru.
The Company has two primary projects situated in the Carajas Mineral Province of northern Brazil being advanced towards a resource definition; the 22,556 hectare Lontra nickel project situated in the Araguaia mobile belt and the Tangara gold, which the Company signed a US$2.8 million option agreement to advance the project with Troy Resources in December 2007. Horizonte is also developing in tandem with Barrick Gold Corporation, the 2,147 hectare Pararapa gold property located in the Department of Arequipa, southern Peru.
Additionally, Horizonte has a generative pipeline of early stage projects in development and has established a 50:50 joint venture company with LGA Mineração e Siderugia Ltda to finance the development of the Crixás, Goiás Velho, Carajás Norte, Lobo and the Araguari, and Itajobi pipeline projects, and identify and acquire suitable bolt-on mineral projects in Brazil. Furthermore Horizonte has signed a US$5.3 million three year joint venture in September 2009 with AngloGold to focus on target generation and potential acquisitions of gold projects in Brazil.