Drill hole B11144 was the first to intersect any significant sulphide mineralization at Sierra Mojada. The company said the hole intercepted 8.45 metres of massive sulphide grading 16.98% zinc, 5.45% lead, and 57.29 grams per tonne (g/t) silver in a previously untested zone 500 metres to the north of the Shallow Silver Zone.
"It is very significant to find a primary high grade sulphide zone at Sierra Mojada which may be the primary source for the extensive oxide mineralization we see in the Shallow Silver and Zinc Zones," Silver Bull president and CEO Tim Barry said.
"This drill hole has opened up a whole new area of exploration potential where we have a one kilometer long untested chargeability anomaly which is almost certainly due to the presence of sulphides and lines up with the B11144 drill hole and old historical sulphide mines.
"While our focus is to continue expanding our growing silver and zinc resources through our 50,000 meter drill program this year it is also now one of our top priorities to further test the size and extent of this new sulphide zone."
Silver Bull said an underground exploration drill program is currently underway targeting underground workings immediately to the south of the Shallow Silver Zone. The company also hopes to drill test a geophysics anomaly which lies to the west of the Shallow Silver Zone later in 2012.
A third NI 43-101 resource update from SRK Consulting is anticipated in the second quarter of 2012.
Given the drilling results to date, Silver Bull anticipates that SRK's next report will show a substantial increase in the silver resource at Sierra Mojada, as well as including a resource for the significant zinc mineralization seen on the project.
Hole B11144 lies along strike to a one kilometre long east-west trending chargeability high identified through a gradient induced polarization (NYSE:IP) survey completed in 2010.
The one kilometer anomaly is thought to represent sulphide mineralization at depth and corresponds to an area historically mined for copper, lead, and zinc massive sulphide mineralization up to 10 metres thick.
Silver Bull said the chargeability anomaly remains open in both the east and west directions.
Sierra Mojada's Shallow Silver Zone currently contains an NI 43-101 compliant resource at a 15 g/t cutoff grade of 47.3 million ounces of silver in the indicated category and 13.8 million ounces in the inferred category.
The mineralized body averages between 30 to 90 metres in thickness, is up to 200 metres wide and has an average grade of just over 50 g/t silver, the company said.
Mineralization remains open in the east, west, south and northerly directions, the company said. Approximately 60 percent of the current 3.2 kilometre mineralized body is at or near surface before dipping at around 10 degrees to the east.
Silver Bull's flagship Sierra Mojada project is located 150 kilometres north of the city of Torreon in Coahuila, Mexico. The company also owns three mineral exploration licences in Gabon, Africa, two of which are currently under joint venture with AngloGold Ashanti(NYSE:AU). These licences are prospective for gold, manganese, and iron ore.