TORONTO, Oct. 10, 2012 /CNW/ - Gran Colombia Gold Corp. (TSX: GCM) is pleased to announce drilling results from the latest underground drill hole in the deep zone at its Marmato Project in Colombia.  Highlights from hole MT-1500 include 1.6 grams per tonne of gold and 1.5 grams per tonne of silver over 618 meters of drilling. The hole also includes 16.9 meters with 35.2 grams per tonne of gold, with a 1.8 meter section containing 159 grams per tonne of gold, from a depth of 872 metres. This deep high-grade mineralization is mainly associated with a zone with several narrow quartz veins, sub-parallel to the core axis, with a true width of about 4.4 meters, which shows several specks of visible gold throughout the interval.

The conclusion of the current deep zone drilling program at Marmato has produced a number of deep gold intersections, which extend mineralization trends to approximately 700 metres below the limit of the current preliminary pit outline and is open at depth.  The deep mineralization is a minimum of 200 metres wide and widens to over 600 meters with depth and is open along strike in both directions. Please refer to Attachment 1 to this press release for an illustrative geological cross section, a copy of which is also available on Gran Colombia's website at www.grancolombiagold.com.

Serafino Iacono, Executive Co-Chairman of Gran Colombia Gold, commented: "The results of this latest drilling reached over 700 meters below the current estimated lower limit of our open pit option and indicate a second zone of mineralization forming a deep body that could be suitable for underground mining. Combined with over 14 million ounces of gold in our current Mineral Resource Estimate, the Marmato Project is one of the richest undeveloped gold projects in the world.  Gran Colombia continues to explore the significance of the deep zone mineralization and its impact on the work undertaken in the pre-feasibility study, which is expected to be completed later this year."

This new zone contains approximately 300 million tonnes of potential mineralization^[1], and is not currently represented in the current total resource estimate at Marmato.  The current Mineral Resource Estimate for the Company's Marmato Project, prepared by SRK Consulting (UK) Ltd. and filed on SEDAR on August 7, 2012, contains 11.8 million ounces of gold in the Measured and Indicated categories and an additional 2.6 million ounces of gold in the Inferred category, at a cut-off grade of 0.3 g/t gold, and 80.3 million ounces of silver in the Measured and Indicated categories and an additional 9.4 million ounces of silver in the Inferred category (see table below).

* Mineral resources are not mineral reserves and do not have demonstrated economic viability. All figures are rounded to reflect the relative accuracy of the estimate. All composites have been capped where appropriate. Mineral resources are reported at a cut-off grade of 0.3 g/t and based on a price of US$1,400 per ounce of gold with gold recoveries of 88 percent and without considering revenues from other metal.

Significant results (greater than 20 gram-metres) are summarized below:

The deep gold mineralization is related to narrow veinlets of quartz-pyrrhotite with minor amounts of pyrite and chalcopyrite and a narrow halo of intermediate argillic alteration. These change upwards to pyrite veinlets with pervasive intermediate argillic alteration. They overprint earlier potassic alteration with porphyry-style quartz veinlets, overlain by propylitic alteration. The porphyry style alteration and veining does not carry mineralization. The copper values are very low and are not of economic interest.

To date, five holes for a total of 4,295 meters have been drilled in the deep zone mineralization.  All of the results to date, together with a map showing the locations of the drill holes, are available on Gran Colombia's website at www.grancolombiagold.com.

Qualified Person

Stewart D. Redwood, Senior Consulting Geologist to the Company, is a qualified person as defined by National Instrument 43-101 - Standards of Disclosure or Mineral Projects and prepared or reviewed the preparation of the scientific and technical information in this press release in respect of the drilling results from the Marmato Project.  Dr. Redwood verified the data disclosed in this news release, including the sampling, analytical and test data underlying the information contained in this news release.  Verification included a review of the quality assurance and quality control samples, and review of the applicable assay databases and assay certificates.

Quality Assurance and Quality Control

In the case of the drilling results referred to herein, the samples were prepared by Acme Analytical Laboratories Ltd (ISO 9001:2008) at their sample preparation facility in Medellin, Colombia, and were assayed at their laboratory in Santiago, Chile.  Gold was assayed by fire assay with atomic absorption spectrophotometer ("AAS") finish.  Samples over 10 g/t gold were assayed by fire assay with gravimetric finish.  Silver was assayed by aqua regia digestion and AAS finish.  Silver samples above 100 g/t were assayed by fire assay with gravimetric finish. Blank, standard and duplicate samples were routinely inserted for quality assurance and quality control.

[1] Under National Instrument 43-101 Standard of Disclosure for Mineral Projects (NI 43-101), this potential tonnage estimate is conceptual in nature as there has been insufficient exploration to define a mineral resource, and it is uncertain if further exploration will result in the targeted discovery being delineated as a mineral resource

About Gran Colombia Gold

Gran Colombia is a Canadian-based gold and silver exploration, development and production company with its primary focus in Colombia. Gran Colombia is currently the largest underground gold and silver producer in Colombia with several underground mines in operation at its Segovia and Marmato Operations. In addition, Gran Colombia is advancing a project to develop a large-scale, gold and silver mine at its Marmato operations.

Additional information on Gran Colombia can be found on the Company's website at www.grancolombiagold.com and by reviewing the Company's profile on SEDAR at www.sedar.com.

This news release contains "forward-looking information", which may include, but is not limited to, statements with respect to the future financial or operating performance of the Company and its projects. Often, but not always, forward-looking statements can be identified by the use of words such as "plans", "expects", "is expected", "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates", or believes" or variations (including negative variations) of such words and phrases, or state that certain actions, events or results "may", "could", "would", "might" or "will" be taken, occur or be achieved. Forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of Gran Colombia to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. Factors that could cause actual results to differ materially from those anticipated in these forward-looking statements are described under the caption "Risk Factors" in the Company's Annual Information Form dated as of March 28, 2012 which is available for view on SEDAR at www.sedar.com. Forward-looking statements contained herein are made as of the date of this press release and Gran Colombia disclaims, other than as required by law, any obligation to update any forward-looking statements whether as a result of new information, results, future events, circumstances, or if management's estimates or opinions should change, or otherwise. There can be no assurance that forward-looking statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, the reader is cautioned not to place undue reliance on forward-looking statements.

Image with caption: "Marmato Project (CNW Group/Gran Colombia Gold Corp.)". Image available at: http://photos.newswire.ca/images/download/20121010_C5677_PHOTO_EN_19107.jpg

SOURCE: Gran Colombia Gold Corp.