|March 31, 2016|
Rosita Mining Exploration Update, Nicaragua
Toronto, Ontario -- March 31, 2016: Rosita Mining Corporation (RST: TSX-V) ("Rosita" or the "Company") is pleased to report the results of a reverse circulation drill program that was carried out in conjunction with in-fill drilling of the Rosita copper-gold-silver bearing stockpiles. In total, 28 short, vertical, RC drill holes totalling 898.9 metres were completed over the R13, R13 West and Tipispan target areas.
Drill testing over these zones was designed to test for shallow, surface-enriched Cu-Au-Ag mineralization. Assay highlights include intercepts of 1.43% copper and 34.29 g/t silver over 16.5 metres at Tipispan and 8.76 g/t gold over 3 metres at R13 West. Geological highlights include recognition of abundant intrusion-hosted gold-copper mineralization in the R13 and Santa Rita pit areas in addition to the skarn-style mineralization that was previously mined.
John Cook, President and CEO, commented, "The intersection of relatively high grading copper mineralization near surface at Tipispan, with good gold values at R13 West, is encouraging and has improved the potential of adding additional resources and emphasises the long term exploration importance to the emerging mine plan we are developing at Santa Rita."
Significant mineralization was intersected at the Tipispan target in drill hole 5783 (see figure); this hole intersected 16.5 m of near surface mineralization grading 1.43% copper, 0.08 grams per tonne gold and 34.29 g per tonne silver from 13.5 m to 30 m vertical depth. Importantly, the hole ended in mineralization with the last 1.5 metre sample assaying 1.58% copper and 24.7 grams silver per tonne. Mineralization occurs primarily as chalcopyrite and arsenopyrite in a monzonite intrusive. In addition, the upper part of the hole returned 10.8 g/t Ag over 12 metres from 1.5 to 13.5 metres depth.
A second hole, 5782, located 50 metres to the west, intersected 19.5 metres grading 0.22% copper and 9.81 grams silver per tonne from 19.5 metres to 39 metres vertical depth. This mineralization was hosted as primary and supergene-style in altered monzonite and as supergene-style mineralization in a later barren granite. This intercept was also bound, up-hole, by a relatively silver-rich interval containing 8.5 g/t Ag over 6.0 metres from 13.5 metres to 19.5 metres.
Additional weak, supergene-style mineralization was intersected in holes 5780 and 5781, located 100 metres and 50 metres, respectively, to the west of hole 5782. A high grade artisanal working area that has returned grab samples to 4.4% Cu, 10.8 g/t Au and 91.9 g/t Ag, was not tested during the program.
The Tipispan area is underlain by a Cu-Ag+-Au mineralized monzonite intrusion that is intruded by a series of barren, possibly northwest-trending, granitic dykes. Work to date has just scratched the surface with the recognition of structurally controlled, at-surface, high grade copper mineralization underlain by a larger mineralized monzonite porphyry intrusion. Additional drilling will be required to test both the high grade structures and the potential of a large mineralized body at depth.
Complete results from the four-hole program including a map of the collar locations, are presented in Table 1, located at the end of this release.
R13 and R13 West
Drill testing over the R13 and R13 West zones was designed to test for shallow, surface-enriched Cu-Au- Ag mineralization along two, interpreted, northeast-trending zones of copper mineralization suggested by historic drill records; these records presented drill intercepts containing up to 0.98% Cu over 79.9 metres. However, no 'from'-'to' data was reported on the historic plan maps. Shallow drill holes completed over the R13 and R13 West Zones did not return any significant, near-surface-enriched mineralization, however, near-surface, diorite-hosted, Au-Cu mineralization was intersected in several areas. The R13 West Zone returned a best value of 8.76 g/t Au and 0.02% Cu over 3 metres and the R13 Zone returned a best value of 0.347 g/t Au and 0.07% Cu over 13.5 metres. This type of diorite-hosted mineralization is similar in character to a 1998 Greenstone Resources hole, HRR13-002 that returned 0.72% Cu, 0.24 g/t Au and 21.94 g/t Ag over 33.0 metres from 184.5 to 217.5 metres. There is a possibility that the holes were not drilled deep enough.
Diorite is also the host to B2 Gold's and Calibre Mining's Primavera deposit, located approximately 7 km to the south, which displays grades in the centre of the zone to 0.78 g/t Au and 0.30% Cu over 261.7 metres and nearby peripheral grades of 0.21 g/t Au and 0.13% Cu over 90.0 metres (Calibre website March 29, 2016).
Drilling in the R13 and R13 West area has returned common intercepts of Cu-Au-Ag, Au-Cu-Ag and Au mineralized intervals that are hosted by skarn, andesite and diorite. The combination of the mineralization types suggest a large scale, multi-episodic mineralizing event that requires more work in order to properly evaluate.
Regional Exploration -- New Discovery
Recent work carried out by Calibre and B2Gold, on their adjacent project, has identified a new zone of significant gold-bearing skarn mineralization located approximately 2.5 km northwest, along strike of Rosita's untested El Rastro Zone (see figure). Calibre's/B2 Gold's work has returned augur samples across a 105 metre wide zone that averaged 5.47 g/t gold. Rosita's sampling at El Rastro has returned 2.90 g/t gold and 1.18 % Cu; the El Rastro zone is hosted by an approximately 300 metre long hill of garnet skarn that is currently being mined for its gold content by local miners.
2016 Operating Plan
Rosita's strategic focus in 2016 is to advance the Santa Rita stockpiles towards a production decision by the fourth quarter of this year. Metallurgical testing will focus on additional gold leaching test work and SART recovery of copper "Calibre News Release Jan. 25, 2015". SART (sulphidization, acidification, recycling and thickening) is an industry standard process for the recovery and recycling of cyanide in gold-copper ores and has been adapted for the treatment of gold-bearing mineralization with high copper content.
Rosita plans to complete this additional test work on both stockpile and tailings samples leading to an optimized process flow design for the project.
The Santa Rita stockpiles and tailings were the subject of an updated NI 43-101 resource estimate which was completed earlier this year. Santa Rita hosts indicated resources of 6.46 million tonnes grading 0.47 grams gold and 0.5% copper per tonne and Inferred resources of 3.47 million tonnes grading 0.46 grams gold and 0.61% copper per tonne.
For complete details, please reference the NI 43-101 resource estimate study which is available at www.sedar.com
Quality Assurance-Quality Control
All samples were collected and transported by Rosita employees to the Bureau Veritus Mineral Laboratories in Managua, Nicaragua for preparation. Samples were assayed in Vancouver using standard fire assay methods with AAS finish for Au and Aqua Regia digestion ICP-ES analysis for Cu and Ag. Certified standards, blanks and duplicates were inserted by Rosita in the sample stream at a rate of one per 30 samples.
John Cook, MIMMM, a Qualified Person, as defined by NI 43-101, has read and approved the contents of this press release.
About Rosita Mining Corporation
Rosita is a junior mining and exploration resource company focused on growing shareholder value through the development of near-term mining opportunities and advancing accretive exploration opportunities.
Rosita's current high priority copper-gold-silver supergene/skarn/porphyry target is the Rosita project in Nicaragua located 275 kilometres northeast of Managua.
For additional information, please visit our website which is under construction at www.rositaminingcorp.com.
For further information, contact:
John Cook, President and CEO
Telephone: +1 416 200 8073
Nick Tintor, Chairman
Telephone: +1 416 987 0855
This news release includes certain forward-looking statements or information under applicable Canadian, U.S. and other securities laws. All statements other than statements of historical fact included in this release, including, without limitation, statements regarding the future plans, objectives or expectations of Rosita are forward-looking statements that involve various risks and uncertainties. There can be no assurance that such statements will prove to be accurate and actual results and future events could differ materially from those anticipated in such statements. Important factors that could cause
actual results to differ materially from the plans of Rosita or expectations include risks relating to the fluctuating gold prices, possibility of equipment breakdowns and delays, exploration cost overruns, availability of capital and financing, general economic, market or business conditions, regulatory changes, timeliness of government or regulatory approvals and other risks detailed herein and from time to time in the filings made by Rosita with securities regulators. Rosita expressly disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events or otherwise except as otherwise required by applicable securities legislation. Neither the TSX Venture Exchange, its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange, nor the OTCQX accepts responsibility for the adequacy or accuracy of this release.
Cautionary Note to U.S. Investors Regarding Mineral Reporting.
Rosita prepares its disclosure in accordance with the requirements of the securities laws in effect in Canada, which differ from the requirements of United States securities laws. Terms relating to mineral resources in this press are defined in accordance with Canadian National Instrument 43-101 --- Standards of Disclosure for Mineral Projects ("NI 43-101") and the Canadian Institute of Mining, Metallurgy and Petroleum (the "CIM") --- CIM Definition Standards on Mineral Resources and Mineral Reserves, adopted by the CIM Council, as amended, which standards differ significantly from the discourse permitted by the United States Securities and Exchange Commission requirements and terminology set forth in SEC Industry Guide 7. Accordingly, information contained in this press release and the public filings of Rosita containing descriptions of mineral deposits may not be comparable to similar information made public by U.S. companies subject to the reporting and disclosure requirements under the United States federal securities laws and the rules and regulations thereunder.
This news release does not constitute an offer to sell or a solicitation of an offer to buy any securities in the United States.
Table 1 -- 2015 RC Drill Program - Significant Results (1)
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