Jun 12 2012
Silver Bull Resources Inc. is pleased to provide an update on a planned 3,000 meter underground drill program to target a high grade zone of silver within the "Shallow Silver Zone".
Highlights include:
- An underground "core" drill program which will target a "high grade" silver zone defined by historical "Long Hole" drilling and channel samples.
- Of the 150 long holes which define the "high grade" zone, 75 holes have average weighted intercepts >80g/t Ag and include; 472g/t Ag over 17 meters, 447g/t Ag over 9 meters, 348g/t Ag over 21 meters, 322g/t Ag over 16 meters, and 363g/t Ag over 10 meters.
- A 500m east-west trending strike to the high grade zone that remains open towards the east.
- Over 70% of the long holes which define this area have ended in mineralization.
- Increased "confidence" in the 2,700 historical long hole data set – which represents 37,873 meters of underground drilling, thereby increasing its influence within the deposit
Underground Drill Program: Silver Bull plans to commence a 3,000 meter underground drill program starting in mid-June targeting a 500 meter long "high grade zone" of silver defined by historical "long holes" – a drill hole averaging between 10 meters to 20 meters in length that "grinds" through the rock to produce a "rock chip" sample and underground channel samples. There are 2,700 long holes within the historical data set that represent over 37,873 meters of drilling. A selected summary of these holes is shown in the table below.
Although the long hole assay results have all been analyzed by ALS Chemex Labs Ltd, a reputable independent laboratory, the influence of the long hole data set in Silver Bull's recent NI 43-101 resource update on the "Shallow Silver Zone" released on May 22, 2012 and completed by SRK Consulting (Canada) Inc. Vancouver, ("SRK") has been severally restricted due to the potential for contamination and sample loss via the washing out of "fines" from the long hole rock chip samples by water used in the drilling process. Within Silver Bull's latest resource the long holes and channel samples were restricted to a 5m x 5m x 20m sphere of influence, whereas regular core drill holes, due to their much higher degree of confidence, had a much larger 100m x 140m x 150m sphere of influence, and hence, a much larger influence on the size and grade of the deposit. After discussion with SRK it has been agreed that by twinning a number of these long holes with the more reliable "core" drilling method and then comparing and confirming the assay results with nearby long holes we hope to increase the confidence of the entire long hole data set. If there is a high correlation this will allow SRK to give the long holes a much wider sphere of influence in a future NI43-101 resource report.
The 3,000 meter underground drill program will initially pick 5 or 6 stations within the high grade zone and "twin" the surrounding long holes for a direct assay comparison. In addition, because over 70% of the long holes ended in mineralization, the drill program will also look to push the holes further to find the extent of the ore body within this zone. A third aspect of the program will be to infill areas where there are "gaps" in the historical work.
To complete the program Silver Bull will use its own Termite underground drill rigs which can drill 40 to 50 meter BQ sized core holes. Historically, recovery in this area has been poor so an emphasis will be placed on achieving good core recovery. Because much of the drilling will happen in areas which already have drill stations prepared there will be very minimal preparation needed for this underground drill program.
Subject to positive assays results, management believes this is a low risk drill program which will increase both the number of silver ounces in the Shallow Silver Zone and likely the overall grade of the deposit. It will also better define the "high grade" core we see at the eastern end of the Shallow Silver Zone.
Because much of the high grade zinc resource seen at Sierra Mojada has also been defined with long holes and channel samples this same approach of twinning selected long holes will eventually be applied to the high grade zinc mineralization which sits adjacent to, and immediately underneath the Shallow Silver Zone.
Tim Barry, President, CEO and director of Silver Bull states, "When we consider that the drills will be starting off underground in high grade silver mineralization, and drilling in an area with a tremendous amount of historical work which already defines this zone we see this as a very low risk program which should add both silver ounces to the deposit, and increase the overall grade within the Shallow Silver Zone. The three goals of this program are; 1) increase the confidence of the 2,700 long hole data set, 2) define the extents of the ore body by drilling through the known mineralization and into mineralized rock, and 3) infill any gaps we have in the historical data set. This will also be extremely cost effective as we will be using our own drills to do this work and there is very little preparation that needs to be done to the underground workings."
In addition to the planned underground drilling program Silver Bull continues to also push its extensive metallurgical program lead by George Rawsthorne on the silver and zinc mineralization, as well as continuing the mapping and prospecting of a number of the Dormidos and Palomas Negros prospects - areas which are defined by extensive underground workings and what appears to be similar mineralization to the Shallow Silver Zone. In light of the current difficult market conditions and the low risk and low cost nature of the underground program, management has decided to suspend its surface drilling program for the moment. This drilling had been targeting the extensions of the Shallow Silver Zone to west and the north as well as a number of near resource exploration targets.
About the Shallow Silver Zone and Zinc Zones; The "Shallow Silver Zone" is an oxide silver deposit hosted along an east-west trending fracture-karst system set in a cretaceous limestone-dolomite sequence. The mineralized body averages between 30m – 120m thick, up to 200m wide and has 3.688Mt of "measured" silver mineralization at an average grade of 57g/t at a 15g/t cutoff, 45.175Mt of "indicated' silver mineralization with an average grade of 45g/t at a 15g/t cutoff, and 8.162Mt of "inferred" silver mineralization with an average grade of 40g/t at a 15g/t cutoff and remains open in the east and west directions. Approximately 60% of the current 3.8 kilometer strike length is at or near surface before dipping at around 6 degrees to the east.
In addition to the silver mineralization, a significant zinc oxide body of 997 million pounds of zinc in the "measured and indicated" category, and 108 million pounds of zinc in the "inferred" category lies immediately adjacent to, and directly underneath the silver mineralization. Further to this, an "exploration target" estimated at between 4-6 million tonnes grading between 8.0-8.4 percent lies as an extension to this zinc body at the eastern end of the mineralization. The exploration target is conceptual in nature, there has been insufficient exploration to define a mineral resource and it is uncertain if further exploration will result in the target being delineated as a mineral resource. The exploration target has been defined by historical data containing 3,733 channels and 1,045 long holes and comprises of approximately 70% of the data within these zinc zones, but has too few drill holes to delineate a mineral resource.
Sample Analysis
All samples have been analyzed at ALS Chemex in North Vancouver, BC, Canada. Samples are first tested with the "ME-ICP41m" procedure which analyzes for 35 elements using a near total aqua regia digestion. Samples with silver values above 100ppm are re-analyzed using the Ag-GRA21 procedure which is a fire assay with a gravametric finish. Samples with zinc, lead, and copper values above 10,000ppm (1%) are re-analyzed using the AA46 procedure which is a near total aqua regia digestion with an atomic absorption finish.
About Silver Bull: Silver Bull is a US registered mineral exploration company listed on both the NYSE MKT and TSX stock exchanges and based out of Vancouver, Canada. The flag ship "Sierra Mojada" project is located 150 kilometers north of the city of Torreon in Coahuila, Mexico and is highly prospective for silver and zinc. Silver Bull also owns three mineral exploration licenses in Gabon, Africa, two of which are currently under joint venture with AngloGold Ashanti. These licenses are prospective for gold, manganese, and iron ore. The technical information of this news release has been reviewed and approved by Tim Barry, MAusIMM, a qualified person for the purposes of National Instrument 43-101.
On behalf of the Board of Directors
"Tim Barry"
Tim Barry, MAusIMMChief Executive Officer, President and Director
Cautionary Note to U.S. Investors concerning estimates of Measured, Indicated and Inferred Resources: This press release uses the terms "measured resources", "indicated resources" and "inferred resources" which are defined in, and required to be disclosed by, NI 43-101. We advise U.S. investors that these terms are not recognized by the United States Securities and Exchange Commission (the "SEC"). The estimation of measured and indicated resources involves greater uncertainty as to their existence and economic feasibility than the estimation of proven and probable reserves. U.S. investors are cautioned not to assume that measured and indicated mineral resources will be converted into reserves. The estimation of inferred resources involves far greater uncertainty as to their existence and economic viability than the estimation of other categories of resources. U.S. investors are cautioned not to assume that estimates of inferred mineral resources exist, are economically minable, or will be upgraded into measured or indicated mineral resources. Under Canadian securities laws, estimates of inferred mineral resources may not form the basis of feasibility or other economic studies.
Disclosure of "contained ounces" in a resource is permitted disclosure under Canadian regulations, however the SEC normally only permits issuers to report mineralization that does not constitute "reserves" by SEC standards as in place tonnage and grade without reference to unit measures. Accordingly, the information contained in this press release may not be comparable to similar information made public by U.S. companies that are not subject NI 43-101.
Cautionary note regarding forward looking statements
This news release contains forward-looking statements regarding future events and Silver Bull's future results that are subject to the safe harbors created under the Securities Act of 1933 (the "Securities Act") and the Securities Exchange Act of 1934 (the "Exchange Act") and applicable Canadian securities laws. Forward-looking statements include statements regarding measured, indicated and inferred resource estimates, the anticipated scope and targets of future drilling in the Shallow Silver Zone, the ability to increase the confidence of the long hole data set, the ability to increase the resource and overall grade at the Sierra Mojada project, and the ability to delineate a zinc resource in the zinc exploration target. These statements are based on current expectations, estimates, forecasts, and projections about Silver Bull's exploration projects, the industry in which Silver Bull operates and the beliefs and assumptions of Silver Bull's management. Words such as "expects," "anticipates," "targets," "goals," "projects," "intends," "plans," "believes," "seeks," "estimates," "continues," "may," variations of such words, and similar expressions, are intended to identify such forward-looking statements. Forward-looking statements are subject to a number of assumptions, risks and uncertainties, many of which are beyond our control, including such factors as the results of exploration activities and whether the results continue to support continued exploration activities, unexpected variations in ore grade, types and metallurgy, volatility and level of commodity prices, the availability of sufficient future financing, and other matters discussed under the caption "Risk Factors" in our Annual Report on Form 10-K for the fiscal year ended October 31, 2011 and our other periodic and current reports filed with the SEC and available on www.sec.gov and with the Canadian securities commissions available on www.sedar.com. Readers are cautioned that forward-looking statements are not guarantees of future performance and that actual results or developments may differ materially from those expressed or implied in the forward-looking statements.
Source:
Silver Bull Resources, Inc.