More info - Santa Barbara Mine (and La Cigarra district)
As we know, it has been postulated that our La Cigarra district is positioned along a dilational structural fault line, which results in pull-apart basins at multiple locations. If this comes to fruition then it will also likely confirm that the mines of San Francisco de Oro and Santa Barbara sits along this La Cigarra fault line, in a completely separate pull-apart basin than Northair`s current La Cigarra resource. I believe that San Francisco de Oro is the north end of that pull-apart basin and Santa Barbara represents the south end. I looked at some pictures and maps to get a sense of the topography of that area and found that both mines appear to be located in valley type areas with perhaps mineralization being within the valley and perhaps also going partly up sides of mountains. This is consistent with La Cigarra and also consistent with the pull-apart basin concept, where things (salt, oil, water, minerals, etc.) are deposited and gets trapped within the sunken ground of the basin. In addition, from results of magnetic surveys, structural info and boots on the ground observations, Northair has further highlighted potential for a separate pull-apart basin to the north of our La Cigarra resource basin and also a separate one to the south. The one to the south is located halfway between our current resource triangle area and the well resourced San Francisco/Santa Barbara area (potential separate resource basin), along the same structural fault. The San Francisco/Santa Barbara mine area has over 800 million ounces of past production and current resource silver, plus some gold and huge amounts of zinc, lead and copper. I will be very surprised if we don`t eventually discover areas with meaningful mineralization within our (potential) south pull-apart basin, located halfway between our current silver resource basin and the San Francisco/Santa Barbara basin - if not starting from surface (if the basin has been covered up) then starting somewhere at depth. Though, I`m thinking this potential South Basin might have more base metal content (than our current La Cigarra resource) along with good silver and gold content. I`m finding the Santa Barbara resource to be interesting. Firstly, it goes down to a depth of 900 metres and is still open I think. It is a silver, gold, copper, zinc and lead deposit, similar to San Francisco de Oro. It`s not clear which metals dominated the top layer hundreds of years ago, but it appears that zinc and lead dominated the middle layer of the deposit (though also included the other metals). However, it appears as if copper is the dominating metal at lower depths. It will be interesting to see how low the resource goes. I can`t locate any Santa Barbara stats for 2014, but the mine produced 63.8K tonnes of zinc in 2013, with 29.4K tonnes of lead and 14.4K tonnes of copper. I don`t know what the 2013 silver and gold production looks like, but it was 4.5 million ounces of silver in 2011 with 3,661 ounces of gold. The mine is owned by Southern Copper, which is a subsidiary of Grupo Mexico. Santa Barbara employs 940 people and has a 6,000 tonne per day concentrator milling capacity. It consists of 3 underground mines and a flotation plant. The ore bodies are formed mainly by quartz veins and ore can be found to be several kilometres in length. Of note, La Cigarra has quartz veins as well, but La Cigarra also has wide disseminated mineralization, which is what enables the wide widths for bulk tonnage mining. The wide La Cigarra silver deposit is a bit unique for Mexico. The Santa Barbara silver/base metal deposit (at least at depth) is probably more traditional for Mexico. Of note, gold was discovered in the district in 1536, but the recent round of mining activity began in 1913. Even though there is a long production history, all signs point to Santa Barbara having resource potential to be in production for decades longer. Four types of mining methods are used or have been used in the mine: shrinkage, long holes, cut and fill, horizontal tajeo.