Integra Resources Outlines Initial Resource Estimate for DeLamar Gold-Silver Project and Appoints Max Baker as Vice President Exploration

TORONTO, Oct. 10, 2017 (GLOBE NEWSWIRE) -- Integra Resources Corp. (CSE:ITR) (the “Company” or “Integra”) is pleased to announce that it has completed an initial resource estimate on the DeLamar Gold and Silver Project (“DeLamar”, the “Project”, or the “Property”) located in southwestern Idaho.  This announcement follows recent notice of the proposed transaction (the “Transaction”) whereby Integra has agreed to acquire 100% of DeLamar from a wholly-owned subsidiary of Kinross Gold Corporation (TSX:K) (“Kinross”).  Key Transaction terms of the acquisition are outlined in Integra’s news release dated September 15, 2017. To view the Transaction news release, please click on the following link:

http://integraresources.com/17-09-18.pdf

The Inferred resource is defined by 1,550 historical drill holes drilled to an average depth of only 120m and delineates the remaining ‘open-pit’ oxide, partly oxidized and unoxidized mineralization at DeLamar, which is hosted within felsic volcanics.  The resource estimate incorporates roughly 143,000m of historic drilling into the global resource for the Property. Resource work for DeLamar was completed by Mine Development Associates (“MDA”) of Reno, Nevada. A sensitivity analysis of the grade and tonnage relationships at a variety of cut-off grades (pit constrained) is shown in Table 1 of this release.  A final 43-101 Technical Report will be filed on SEDAR in the coming weeks.

Key Highlights:

• Robust initial inferred resource for DeLamar:
  
  • 0.3 g/t AuEq cut-off grade: 117,934,000 tonnes grading 0.41 g/t gold and 24.34 g/t silver, for a total of 1,592,000 oz of gold and 91,876,000 oz of silver, or 2,673,000 oz of gold equivalent (“AuEq”) averaging 0.7 g/t AuEq
  
  • As demonstrated in the included sensitivity analysis below, increasing the AuEq cut-off grade to 0.75 g/t results in the following changes to the grade and tonnes; 33,716,000 tonnes grading 0.69 g/t gold and 48.69 g/t silver, for a total of 735,000 oz of gold and 52,747,000 oz of silver, or 1,356,000 oz of AuEq averaging 1.26 g/t AuEq
  
  • Au Equivalent = Au g/t + (Ag g/t ÷ 85)
   
• Project exhibits significant exploration upside, remaining open at depth, with limited historical deep drilling below 250 meters. The limited deep drill hole data available dating back to the early 1990’s includes intercepts which have intersected the series of deeper high-grade veins, including:
  • 105.4 g/t Au and 41.0 g/t Ag (105.9 g/ AuEq) over 10.7 metres;
  • 10.1 g/t Au and 116.6 g/t Ag (11.5 g/t AuEq) over 18.3 metres;
  • 10.1 g/t Au and 188.1 g/t Ag (12.3 g/t AuEq) over 18.3 metres
   
• Excellent metallurgical gold-silver recoveries in historical conventional milling past production, and column leach test work designed to approximate potential heap-leaching, demonstrate the potential viability of both options for any future development.
  
  
• Introduction of Max Baker, Ph.D., appointed as VP Exploration: Reno-based, over 35 years exploration experience in Low Sulphidation Epithermal deposits, previously worked with Newcrest Mining, Rennison Gold Fields and Mount Isa Mines.

In concluding comments regarding the project, MDA reported, “Exploration potential for additional bulk-tonnage mineralization on the DeLamar project appears to be significant. Essentially all of the modeled mineralization is open at depth, and, considering the shallow extents of a high percentage of the historical holes, the potential to expand mineralization that is potentially mineable by open-pit methods exists.” In reference to high-grade gold-silver at DeLamar, MDA stated, “In addition to the bulk-tonnage potential, there is also strong potential for the discovery of high-grade vein-type mineralization similar to that mined in the late 19th and early 20th centuries.  MDA recommends further work to investigate the amenability to Heap Leaching, concluding that, “It is possible that some portion of the current resources, perhaps a large portion, could be amenable to heap-leach processing.”

George Salamis, President and CEO commented: “With the maiden resource results in hand, we are excited by both this significant initial inferred resource estimate on the property, and the scenario that has been laid out for current and future shareholders. It is one that highlights significant potential for further near surface bulk tonnage low-grade resources as well as the series of high grade veins inferred from historic drill intercepts at deeper levels, to occur beneath the lower grade open-pit resource defined by MDA.  The DeLamar Project comprises a key land position within the greater DeLamar-Florida Mountain district, which we believe hosts one of the largest gold-silver low sulphidation epithermal systems in the Western US.  From our analysis of the database, we can clearly see where exploration needs to focus to test both the immediate extensions of low-grade near-surface gold-silver and deeper series of high-grade gold-silver veins, on a project that has only been drilled to an average depth of 120m from surface.”  Mr. Salamis added, “We are also very pleased to welcome Max Baker as Vice President of Exploration for Integra Resources. Max’s track-record of discovery, familiarity with deposits of this type, and more specifically with the DeLamar deposit itself, make him the right choice to oversee exploration for Integra and its shareholders."

Summary of the Initial Mineral Resource Estimate

Table 1.  Sensitivity analysis of grade and tonnage at varying pit-constrained cut-off grades on the DeLamar Project

1. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
2. Mineral Resources are comprised of all model blocks with gold-equivalent values greater than or equal to 0.30 g/t that lie
within an optimized pit and below the as-mined surface.
3. Gold equivalent = g Au/t + (g Ag/t ÷ 85)
4. Rounding may result in apparent discrepancies between tonnes, grade, and contained metal content.
5. The estimate of mineral resources may be materially affected by geology, environment, permitting, legal, title, taxation, socio-political, marketing or other relevant issues.
6. The effective date of the mineral resource estimate is October 1, 2017.

Key Resource Estimation Highlights

• DeLamar project initial inferred resource: 0.3 g/t Au Equivalent Cut-Off:  117,934,000 tonnes grading 0.41 g/t gold and 24.34 g/t Ag, for a total of 1,592,000 oz of gold and 91,876,000 oz of silver. In total, 2,673,000 oz of AuEq grading 0.7 g/t AuEq
  
  
• At a 0.75 g/t Au Equivalent Cut-off: 33,716,000 tonnes grading 0.69 g/t gold and 735,000 oz of gold and 52,747,000 oz of silver ( 1,356,000 oz of AuEq grading 1.26 g/t AuEq)
   
• The gold and silver mineral resources at DeLamar were modeled and estimated by:
  
  • evaluating the drill data statistically;
  • separately interpreting gold and silver mineral domains on sets of 320°-looking cross sections spaced at 30.48-meter intervals;
  • analyzing the modeled mineralization spatially and statistically to aid in the establishment of estimation and classification parameters; and
  • interpolating grades into a three-dimensional block model using the cross-sectional gold and silver mineral domains to control the estimation
   
• The reported resources have been constrained within an optimized pit shell using a gold price of $US1,300/ounce and a silver price of $US18/ounce of silver. These metal prices were also used to calculate gold equivalent cut-off grade and contained ounces
   
• Additional inputs for pit-optimization include: Mining – $2.20/tonne mined, Milling – $10.00/tonne milled, G&A – $4,000,000/yr, Tonnes per year processed – 4,760,000, Gold Recovery – 95%, Silver Recovery – 80%
   
• The resource estimate is based on 1,575 reverse circulation holes, conventional rotary holes, and diamond core holes drilled from the mid 1970s to the early 1990s
   
• The existing gold and silver resources, defined by the historic shallow drilling, are hosted in Miocene-aged porphyritic rhyolite/latite volcanic flows that represents the upper part of a well studied and recently re-interpreted low-sulphidation epithermal system
   
• A technical report on the initial resource estimate will be prepared in accordance with National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”) and filed within 45 days of this news release on Integra’s issuer profile on SEDAR at www.sedar.com

To view a plan map showing location of all zones on the Property, with the resource limit outlined, please click the following link:

http://www.integraresources.com/assets/files/2017-10-10-delamar-outline-site-map.pdf

To view an idealized cross section with geological and structural interpretation at DeLamar, please click the following link:

http://www.integraresources.com/assets/files/2017-10-10-delamar-cross-section.pdf

Focus of Future Drilling and Potential for Resource Expansion at DeLamar

Management’s analysis of the data used in the resource estimate supports the view that strong potential exists for further resource expansion and new discoveries of low-grade and high-grade gold mineralization. This view is underpinned by a myriad of apparent factors including: a) the lack of overall deeper drilling (current average depth: 120m),  b) the project was last drilled approximately 25 years ago and has not seen any modern exploration techniques employed, and c) past exploration focus was solely on near surface, bulk-tonnage low-grade mineralization despite the fact that the historical mining record at DeLamar reported underground high grade mining of a series of moderate to steeply dipping veins with reported gold-silver cut-offs above 15 g/t and average mined gold-silver contents sometimes in excess of 60 g/t.

With respect to this high-grade potential, numerous past near surface drill holes designed to test for low-grade open-pitable material in fact pieced through the rhyolitic host rock and into underlying basalt units, reporting high gold and silver grades within less than 200 meters of surface as seen in Table 2 below.

Table 2. Highlighted Drill Intercepts Below Current Mining Surface at the DeLamar Project

*Drill intercept lengths only are reported in the tabulations; it is estimated that true width will be approximately 60% or less of the reported drill intercept length.

Assuming completion of the Transaction, the Company will use a significant portion of the proceeds on a 20,000 meter (predominantly RC) drill program, tentatively scheduled to commence in Q1 2018, aimed at specifically targeting low-grade and high grade gold-silver mineralization on extension from previous drill intercepts in areas such as Sommercamp, Sullivan Gulch, South Wahl, and elsewhere. In addition to ground geophysical surveys, surface sampling, and reconnaissance work, Integra will conduct further metallurgical test work on near surface, low-grade material designed to further highlight DeLamar’s potential amenability to Heap Leaching. Data from metallurgical Column Leach testing conducted on neighbouring mineral claims in the past points to high gold leach extraction from oxidized and partially oxidized mineralization and suggests that heap leaching of crushed and/or run of mine mineralization may be a viable option to look at in future studies. Previous column leach test work conducted on surface mineralization from these claims (presumably partially or fully oxidized) yielded recoveries of up to 85% gold and 35% silver.

Assuming completion of the Transaction, planned extensive drilling campaigns and other technical studies will form the basis of future periodical resource estimate updates and development analyses that the company contemplates undertaking in the next 18 to 24 months at DeLamar. Given the past mining and conventional milling history of the project with economic recoveries derived from oxide, transitional and sulphide mineralization in the historical milling record and in test work, the company will undertake additional technical studies on both conventional milling and heap leaching.

DeLamar Project Resource: History of the DeLamar Data

The DeLamar Mine closed in 1998 due to low precious metal prices (below US$300/oz Au) after producing more than 1.6M oz of gold and 100M oz of silver within the district. Roughly half of the historic gold-silver production was produced from the underground mining of a series of high-grade veins between the mid 1800s to early 1900s, in stopes mined at a cut-off of over 15 g/t Au. The remaining half of DeLamar’s historical production was derived from near-surface low-grade bulk-mining and conventional milling of oxidized material and transitional mineralization which took place between 1977 and 1998. In 1998, as a result of low precious metal prices, the DeLamar Project was placed on care and maintenance. No drilling has been conducted on the Property since 1998 and substantial resources, as demonstrated in today’s news release, remain on the Project.

To view a DeLamar property location map, please click the following link:

http://www.integraresources.com/assets/files/2017-10-10-delamar-location.pdf

The DeLamar Property is located in southwestern Idaho in Owyhee County, 80 kilometers southwest of the city of Boise, just west of the historic mining town of Silver City. The Property constitutes roughly 5,300 acres of patented and unpatented claims, and a further 4,100 acres of leased lands. MDA’s estimated resource was constructed using approximately 1,550 drill holes and 143,660m of drilling, where average drill hole depth was less than 120m, with only four holes deeper than 350m. This database was created by MDA using original DeLamar mine digital database files obtained from the current mine site.  The original mine-site information was then subjected to various verification measures, the primary one consisting of auditing of the digital data by comparing the drill-hole collar coordinates, hole orientations, and analytical information in the MDA constructed database against historical paper records in the possession of Integra.

Geology and Mineralization of DeLamar

The DeLamar project is situated in the Owyhee Mountains near the east margin of the mid-Miocene Columbia River – Steens flood basalt province and the west margin of the Snake River Plain.  The Owyhee Mountains comprise a major mid-Miocene eruptive center, generally composed of mid-Miocene basalt flows and younger, mid-Miocene rhyolite flows, domes and tuffs, developed on an eroded surface of Late Cretaceous granitic rocks. 

The mine area and mineralized zones are situated within an arcuate, nearly circular array of overlapping porphyritic and banded rhyolite flows and domes that overlie cogenetic, precursor pyroclastic deposits erupted as local tuff rings.  The porphyritic and banded rhyolite flows and domes were interpreted to have been emplaced along a system of ring fractures developed above a shallow magma chamber that supplied the erupted rhyolites.  This magma chamber was inferred to have been intruded within a northwest flexure of regional north-northwest trending Basin and Range faults, related to the North Nevada Rift.

Two styles of gold-silver mineralization have been recognized: 1) relatively continuous, quartz-filled fissure veins that were the focus of late 19^th and early 20^th century underground high-grade gold-silver mining, and 2) broader, bulk-mineable low-grade gold-silver zones of closely-spaced quartz veinlets and quartz-cemented hydrothermal breccia veinlets. This second type of typically low-grade gold and silver mineralization was bulk mined in the open pits of the late 20^th century DeLamar and Florida Mountain operation, and was processed using conventional milling methods (crushing, gravity, agitated leach).

The gold and silver mineralization at the DeLamar project is best interpreted in the context of the volcanic-hosted, low-sulfidation type of epithermal model.  Various vein textures, mineralization and alteration features, and the low contents of base metals in the district are typical of low-sulfidation epithermal deposits world-wide.

Appointment of Max Baker as Vice-President Exploration

Integra Resources is very pleased to announce the appointment of E. Max Baker, Ph.D., as the company’s Vice President of Exploration. Max has led a 35-year career in the field of mineral exploration world-wide, and has been a key figure on many well-know resource discoveries. Max, based in Reno Nevada, holds a Ph.D. degree in geology from James Cook University in Queensland, Australia.  His career includes work with Renison Goldfields, Mount Isa Mines, and Newcrest Mining, throughout regions including Australia, Southeast Asia, South America, and Europe, following which he moved to North America to work on mineral deposits in the Western US and Canada. Max has a specific wealth of experience with respect to DeLamar, having worked as a consult to Kinross on the operation.

Details of the DeLamar and Florida Mountain Acquisition

On September 17, 2017, Integra announced that it will acquire 100% of the DeLamar Gold and Silver Project from a wholly-owned subsidiary of Kinross for C$7.5 million in cash and the issuance of Integra shares that is equal to 9.9% of all of the issued and outstanding Integra shares upon closing of the Transaction. The DeLamar Project is subject to a retained variable net smelter return (“NSR”) royalty payable to Kinross. Concurrent to the DeLamar transaction, Integra has also signed binding letters of intent (“LOIs”) with two private entities to acquire patented claims in the past-producing Florida Mountain area (“Florida Mountain”), which borders DeLamar to the east.

To view the news release dated September 17, 2017, outing all details of the Transaction, please click on the following link:

http://integraresources.com/17-09-18.pdf

Qualified Person

Unless otherwise indicated, the scientific and technical information contained in this news release has been reviewed and approved by E. Max Baker Ph.D. M. AustIMM, of Reno, Nevada who is a "qualified person" within the meaning of National Instrument 43-101 – Standards of Disclosure for Mineral Projects and is independent of Integra.

About Integra Resources

Integra Resources Corp., formerly, Mag Copper, is a development-stage company engaged in the acquisition, exploration and development of mineral properties in the Americas. The management team comprises the former executive team from Integra Gold Corp.

ON BEHALF OF THE BOARD OF DIRECTORS
George Salamis
CEO & President

CONTACT INFORMATION

Corporate Inquiries: Chris Gordon, chris@integraresources.com
Or visit the company website: www.integraresources.com

82, Richmond St East, Suite 200
Toronto, Ontario, Canada
M5C 1P1

This news release contains "forward-looking information" and "forward-looking statements" (collectively, "forward-looking statements") within the meaning of the applicable Canadian securities legislation. All statements, other than statements of historical fact, are forward-looking statements and are based on expectations, estimates and projections as at the date of this news release. Any statement that involves discussions with respect to predictions, expectations, beliefs, plans, projections, objectives, assumptions, future events or performance (often but not always using phrases such as "expects", or "does not expect", "is expected", "anticipates" or "does not anticipate", "plans", "budget", "scheduled", "forecasts", "estimates", "believes" or "intends" or variations of such words and phrases or stating that certain actions, events or results "may" or "could", "would", "might" or "will" be taken to occur or be achieved) are not statements of historical fact and may be forward-looking statements. In this news release, forward-looking statements relate, among other things, to: the completion of the Transaction and the acquisition of the Florida Mountain claims; the anticipated benefits of the Transaction (including the acquisition of the Florida Mountain claims and the Private Placement) to Integra and its shareholders; the timing and receipt of the required stock exchange and regulatory approvals for the Transaction; the timing and ability of Integra to satisfy the conditions precedent to completing the Transaction and the acquisition of the Florida Mountain claims; completion of the Private Placement; anticipated use of proceeds from the Private Placement; statements about the estimation of mineral resources; magnitude or quality of mineral deposits; anticipated advancement of mineral properties or programs; future operations; future exploration prospects; the completion and timing of mineral resource estimates; the length of the current market cycle and requirements for an issuer to survive in the current market cycle; future growth potential of Integra; and future development plans.

These forward-looking statements are based on reasonable assumptions and estimates of management of Integra at the time such statements were made. Actual future results may differ materially as forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of Integra to materially differ from any future results, performance or achievements expressed or implied by such forward-looking statements. Such factors, among other things, include: satisfaction or waiver of all applicable conditions to the completion of the Transaction and the acquisition of the Florida Mountain claims (including receipt of all necessary stock exchange and regulatory approvals or consents, and the absence of material changes with respect to the parties and their respective businesses, all as more particularly set forth in the stock purchase agreement relating to the Transaction which is available under the Company’s issuer profile on SEDAR); possible variations in mineralization, grade or recovery rates; actual results of current exploration activities; actual results of reclamation activities; conclusions of future economic evaluations; ability to close the Private Placement on the proposed terms or at all, the synergies expected from the Transaction and the acquisition of the Florida Mountain claims not being realized; business integration risks; fluctuations in general macroeconomic conditions; fluctuations in securities markets; fluctuations in spot and forward prices of gold, silver, base metals or certain other commodities; fluctuations in currency markets (such as the Canadian dollar to United States dollar exchange rate); change in national and local government, legislation, taxation, controls, regulations and political or economic developments; risks and hazards associated with the business of mineral exploration, development and mining (including environmental hazards, industrial accidents, unusual or unexpected formations pressures, cave-ins and flooding); inability to obtain adequate insurance to cover risks and hazards; the presence of laws and regulations that may impose restrictions on mining; employee relations; relationships with and claims by local communities and indigenous populations; availability of increasing costs associated with mining inputs and labour; the speculative nature of mineral exploration and development (including the risks of obtaining necessary licenses, permits and approvals from government authorities); and title to properties. Although the forward-looking statements contained in this news release are based upon what management of Integra believes, or believed at the time, to be reasonable assumptions, Integra cannot assure its shareholders that actual results will be consistent with such forward-looking statements, as there may be other factors that cause results not to be as anticipated, estimated or intended.

Readers should not place undue reliance on the forward-looking statements and information contained in this news release. Except as required by law, Integra assumes no obligation to update the forward-looking statements of beliefs, opinions, projections, or other factors, should they change, except as required by law.