Silver Bull Resources (TSE:SVB)(NYSE MKT:SVBL) unveiled Thursday a third batch of drill results from its underground drill program in its high grade zinc zone at the Sierra Mojada project in northern Mexico, saying mineralization remains open to expansion in four directions.

The results form part of an underground program that twinned what the company calls a historical “long hole” data set along a high grade silver zone and the underlying and adjacent high grade zinc zone – both located at the eastern end of the current resource. 

The aim of the total 5,000 metre campaign, which concluded last month, was to increase confidence in the historical long hole data set, which represents 38,000 metres of drilling that was either “severely restricted” or discarded in the company’s latest NI 43-101 resource report on the Shallow Silver zone last July. 

The company said the program actually amounted to 6,500 metres of drilling, which resulted in the twinning of around 17% of the historic 38,000 metre data set. Silver Bull is awaiting final results, after which it will start a revised resource update on the Shallow Silver and Zinc zones – expected this quarter. 

Today’s zinc results are the third of five batches from the high grade zinc zone, with the company having just released the tenth batch of high grade silver holes earlier this month. 

Notable zinc holes Thursday include 43.55 metres at 15.65% zinc, including 14.5 metres at 20.26% zinc and 9.30 metres at 15.72% zinc, including 1.95 metres at 28.35% zinc. 

From the results today, widths of intercepts ranged from 1.95 to 43.55 metres, with grades between 9.08% zinc and 28.35% zinc. 

Based on the updated resource report figures, the company is aiming to complete the maiden PEA on the Sierra Mojada project in the third quarter of this year. The PEA will incorporate ongoing work on metallurgical optimization, hydrology, and geotechnical studies and detailed mine plan studies. 

As of July last year, the Shallow Silver Zone hosted a silver resource of 72.1 million ounces in the measured and indicated category, and 10.4 million ounces in the inferred category.