ULAANBAATAR, MONGOLIA--(Marketwire - March 14, 2011) - Robert Friedland, Executive Chairman and Chief Executive Officer of Ivanhoe Mines Ltd. (News - Market indicators)(NYSE:IVN)(NASDAQ:IVN), and Richard Gosse, Vice-President, Exploration, announced today that Ivanhoe and BHP Billiton Ltd. have discovered a new zone of shallow copper-molybdenum-gold mineralization approximately 10 kilometres north of the Ivanhoe Mines Oyu Tolgoi copper-gold mining complex currently under construction in southern Mongolia.
The discovery, known as Ulaan Khud North, extends the known strike length of the Oyu Tolgoi mineralized system by an additional three kilometres to the north, to more than 23 kilometres.
Less than half of the 23-kilometre-long mineralized trend at Oyu Tolgoi has been extensively drill-tested to date. An ongoing exploration program including proprietary, induced-polarization (IP) technology has identified additional exploration and development targets.
"The Ulaan Khud North discovery reinforces our longstanding belief that with continued exploration there is excellent potential to discover new porphyry deposits, rich in copper and gold, which are associated with the world-class Oyu Tolgoi mineralized trend," said Mr. Friedland.
Ulaan Khud North is located on a 19,625-hectare exploration licence that is part of Ivanhoe's joint-venture partnership with BHP Billiton, which was formed in 2005. BHP Billiton has earned a 50% interest in the joint venture, which includes the Ulaan Khud North property, by spending US$8 million in exploration costs and conducting an airborne survey using the proprietary Falcon™ gravity gradiometer system over the Oyu Tolgoi area.
A total of 25 drill holes (UKD031 to 055) totalling 6,561 metres, ranging in depth from 182 metres to 377 metres, defined the new zone of shallow porphyry copper mineralization over an area of 600 metres by 300 metres. Most of the holes are vertical and were drilled on a 100-metre-square grid. The mineralized zone starts beneath 60 to 80 metres of Cretaceous clay and gravels, indicative of a near-surface deposit with open-pit mining potential. Ivanhoe's geologists believe that the near-surface copper mineralization discovered to date at Ulaan Khud North may be part of a much larger deposit.
Mineralization occurs in quartz monzodiorite, similar to mineralized quartz monzodiorites at Oyu Tolgoi. A total of 23 of the 25 drill holes drilled at Ulaan Khud North intersected the mineralized quartz monzodiorite. The mineralization is porphyry-style stockwork, disseminations and massive veins of chalcopyrite, with molybdenite disseminations and veinlets and trace bornite. Many holes encountered mineralization with greater than 1% copper in multiple individual one-metre samples, while almost all holes have longer intervals of mineralization grading greater than 0.3% copper. Numerous post-mineral intrusive rocks cut the mineralized quartz monzodiorite and define the boundaries of most mineralized intervals. (Photos of mineralization found at Ulaan Khud North are attached.)
"The presence of intensively mineralized and altered quartz monzodiorite and basalt xenoliths within the moderately mineralized quartz monzodiorite supports the idea that an earlier phase of stronger mineralization exists at depth and along margins of the area," said Mr. Gosse.
Highlights include:
A full list of intercepts using a 0.2% copper cut-off is shown in Table 1. The true widths of mineralization and post-mineral dykes have yet to be established.
The mineralization at Ulaan Khud North starts as shallow as 60 metres below surface, much higher than the mineralized zone at Hugo Dummett to the south. The fact that Ulaan Khud North occurs in similar Devonian host rocks to Hugo Dummett suggests that the main Oyu Tolgoi porphyry system trend is relatively shallow in this area and that potential for surface-mineable targets still exist within the Oyu Tolgoi trend and Ulaan Khud North in particular.
The Ulaan Khud North property adjoins the Shivee Tolgoi Entrée Gold–Ivanhoe Mines joint-venture property and is about three kilometres north of mineralization found at Ulaan Khud on that licence.
Three-Year Pre-Mining Agreement Received
The Pre-Mining Agreement for the Ulaan Khud North property specifies that Ivanhoe and BHP Billiton have three years to conduct additional exploration, complete an environmental impact study, prepare a final feasibility study and gain approval for the design for the project. The agreement also specifies that a Technical and Economical Study to mine the deposit is required to be delivered to the Mineral Resources Authority of Mongolia (MRAM) by June 30, 2013.
"The Pre-Mining Agreement provides a three-year window to aggressively explore the project and to prepare resource, technical and economic studies. It also paves the way for the Ulaan Khud North Project to obtain all necessary mining permits and approvals," said Mr. Gosse.
Quality Assurance and Quality Control
Stephen Torr, P.Geo., Ivanhoe Mines' Mineral Resource Manager and a qualified person as required by NI 43-101, supervised the preparation of the information in this news release.
The sampling program used at the Ulaan Khud North project comprised collection of core samples taken on one-metre intervals in mineralized zones and two-metre intervals in non-mineralized post-mineral dykes, excluding dykes that extend more than five metres along the core length. Samples of one-half of HQ core were taken for assaying. The core was marked with a continuous cutting line along the middle, parallel to the long axis, to prevent a sampling bias during splitting. Splitting was done with a rock saw flushed continually with water. Samples were placed in cloth bags, sealed with numbered security tags, quality control samples were inserted for monitoring of the assay data and all samples were sent to SGS Mongolia LLC for preparation and assaying. Each batch of 20 samples contained one Standard Reference material, certified for copper-gold, one Field Blank, one Core Duplicate and one Pulp or Crush Duplicate. All samples were assayed for gold, copper, molybdenum, arsenic, silver, lead and zinc.
Upon receipt of assay results, values for Standard Reference Material samples and Field Blanks were tabulated and compared to those from an established Round Robin program. Assay results that deviated from the Round Robin program results beyond pre-set tolerance limits were rejected and subject to re-assay. Check assays were conducted on a regular basis at the rate of one per batch of 20 samples.
About Ivanhoe Mines
Ivanhoe Mines (News - Market indicators)(NYSE:IVN)(NASDAQ:IVN) is an international mining company with operations focused in the Asia Pacific region. Assets include the company's 66% interest in the Oyu Tolgoi copper-gold mine development project in southern Mongolia; its 57% interest in Mongolian coal miner SouthGobi Resources (TSX:SGQ)(HK:1878); a 62% interest in Ivanhoe Australia (ASX:IVA)(TSX:IVA), a copper-gold-uranium-molybdenum-rhenium exploration and development company; and a 50% interest in Altynalmas Gold Ltd., a private company developing the Kyzyl Gold Project in Kazakhstan.
Forward-looking statements
This news release contains forward-looking statements. Forward-looking statements are statements that relate to future events such as Ivanhoe's intent to continue drilling at the Oyu Tolgoi Project. In some cases, you can identify forward-looking statements by terminology such as "may", "should", "expects", "plans", "anticipates", "believes", "estimates", "predicts", "potential" or "continue" or the negative of these terms or other comparable terminology. Forward- looking statements within this release include, but are not limited to the 2011 exploration program for the Ulaan Khud North Project. These statements are only predictions and involve known and unknown risks, uncertainties and other factors that may cause our or our industry's actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by these forward-looking statements. While these forward-looking statements, and any assumptions upon which they are based, are made in good faith and reflect our current judgment regarding the direction of our business, actual results almost always will vary, sometimes materially, from any estimates, predictions, projections, assumptions or other future performance suggested herein. Readers are referred to the sections entitled "Risk Factors" in Ivanhoe Mines' periodic filings with Canadian and U.S. Securities Commissions.