The Mineral Ridge project is located ~6 km northwest of the town of Silver Peak and 56 km southwest of Tonopah in Esmeralda County, Nevada. The property consists of 616 mining claims totalling 5,010 hectares (12,380 acres).
Scorpio Gold holds a 70% interest in Mineral Ridge project with joint venture partner Waterton Global Value L.P. (30%). The Company is currently entitled to receive 80% of cash flow generated in accordance with project agreements and is the operator of the project.
Prior to Scorpio Gold's acquisition in March 2010, Mineral Ridge historically produced ~575,000 ounces of gold, including ~170,000 ounces from open pit and ~405,000 ounces from underground mining operations. Upon acquiring its interest, the Company commenced major site rehabilitation to bring the project to a fully operational status. Pre-production mining commenced in the Drinkwater pit on May 31, 2011 and the Company achieved commercial production status effective January 1, 2012.
Mineral Ridge is a conventional open pit heap leaching operation. Gold and silver bearing solution from the leach pad is collected in the pregnant pond and processed through carbon columns in the ADR plant for recovery of the precious metals from leachate on carbon. Loaded carbon is shipped to Metals Research in Kimberley, Idaho for processing into doré. The doré bars are then delivered to Johnson Matthey's refinery in Salt Lake City for further refining of the precious metals into separate 99.9% pure gold and silver bars.
2015 Mineral Ridge Operations Forecast:
- Production: 40,000 to 45,000 ounces of gold
- Total Cash Cost: US$800 to US$850 per ounce of gold sold
Production in 2015 is scheduled from the Mary and Mary LC pits, and from the Wedge, Bluelite, Solberry and Brodie satellite pits.
Key estimated parameters forming the basis for the 2015 forecast are:
- Average throughput: 2,700 short tons (2,450 metric tonnes) per day
- Average grade: 0.061 ounces per short ton (2.09 grams per tonne) gold
- Waste to ore ratio including development: 7.4 to 1
The Company expects these parameters to fluctuate throughout 2015 and as a result, these parameters should be treated as full-year averages and will not necessarily be reflective of quarterly operating results.
SECOND QUARTER 2015
Gold production at Mineral Ridge in Q2 of 2015 totalled 8,738 ounces of gold a total cash cost of US$800 per ounce of gold sold, Total gold production for the first half ("H1") of 2015 was 20,690 ounces, an increase of 7% from H1 of 2014.
A summary of the Q2 2015 operating and financial results is presented in the Company's July 14, 2015
and August 27, 2015
news releases, with complete details provided in the Q2 2015 Financial Statements
and Management Discussion & Analysis
Highlights for the Second Quarter Ended June 30, 2015 and subsequent events:
Highlights for the Six-Month Period Ended June 30, 2015:
- 8,738 ounces of gold were produced at the Mineral Ridge mine, compared to 9,034 ounces produced during Q2 of 2014.
- Revenue of $12.1 million, compared to $10.6 million during Q2 of 2014, due to a higher number of ounces of gold sold despite a lower average gold price.
- Total cash cost per ounce of gold sold(1) of $800, compared to $815 during Q2 of 2014.
- Mine operating earnings(1) of $2.4 million, compared to $1.0 million during Q2 of 2014, mainly due to lower depletion and amortization.
- Net earnings of $1.7 million ($0.01 basic and diluted per share), compared to $0.6 million ($0.00 basic and diluted per share) during Q2 of 2014.
- Adjusted net earnings(1) of $1.8 million ($0.01 basic and diluted per share), compared to $0.5 million ($0.00 basic and diluted per share) during Q2 of 2014.
- Adjusted EBITDA(1) of $2.9 million ($0.01 basic and diluted per share), compared to $3.4 million ($0.02 basic and diluted per share) during Q2 of 2014.
- Cash flow from operating activities(1) of $4.6 million, compared to $2.2 million during Q2 of 2014, mainly as a result of a decrease in inventory level.
- Effective July 28, 2015, the Goldwedge property was put on care and maintenance.
- On August 14, 2015, the Company closed a $6 million principal amount debt financing that will be mainly used to fund the exploration and development of the Company's Mineral Ridge property and for general working capital purposes. The debt bears interest at a rate of 10% per annum, paid quarterly in arrears, has a three year term, and is secured against all of the assets of the Company and its subsidiaries.
(1) This is a non-IFRS measure; refer to Non-IFRS Measures section of this press release and the Company's Management Discussion & Analysis for Q2 of 2015 for a complete definition and reconciliation to the IFRS results reported in the Company's financial statements for Q2 of 2015.
- 20,690 ounces of gold were produced at the Mineral Ridge mine, compared to 19,328 ounces produced during the six months ended June 30, 2014.
- Revenue of $24.4 million, compared to $23.9 million during the six months ended June 30, 2014, mainly due to increased production which resulted in a higher number of ounces of gold sold, but at a lower average gold price.
- Total cash cost per ounce of gold sold(1) of $798, compared to $803 during the six months ended June 30, 2014.
- Mine operating earnings(1) of $4.5 million, compared to $2.4 million during the six months ended June 30, 2014, mainly due to lower depletion and amortization.
- Net earnings of $2.5 million ($0.01 basic and diluted per share), compared to net earnings of $1.0 million ($0.00 basic and diluted per share).
- Adjusted net earnings(1) of $1.4 million ($0.01 basic and diluted per share), compared to $0.9 million ($0.00 basic and diluted per share) during the six months ended June 30, 2014.
- Adjusted EBITDA(1) of $4.7 million ($0.02 basic and diluted per share), compared to $7.2 million ($0.04 basic and diluted per share) million during the six months ended June 30, 2014.
- Cash flow from operating activities(1) of $9.0 million, compared to $5.4 million during the six months ended June 30, 2014, mainly as a result of a decrease in inventory level.
In its July 21, 2014
news release, the Company reported on an updated Life of Mine Plan ("LOM Plan") for the Mineral Ridge Operation that included the Drinkwater, Mary, Mary LC, and the five satellite deposits, Brodie, Bluelite, Solberry, Wedge and Oromonte. (see Mineral Reserve & Resource Estimates
). With completion of mining of the Drinkwater deposit in Q3 2014, Mary is now the main deposit currently in production. Development of the Mary LC pit commenced in Q1 2014 and attaining commercial production status at Mary LC is expected in Q4 2015. Open pit mining at the Solberry deposit commenced in Q2 2015. Pre-production development work at the Bluelite deposit is in progress with open pit production scheduled in Q3 2015.
Operations Area Map
(PDF 4.3 Mb)
Mary - Mary LC Deposit
The Mary deposit is located immediately southeast of the Drinkwater pit. Scorpio Gold commenced pre-stripping operations in the Mary pit in December 2011 and initial ore production in Q2 2012. Exploration drilling in 2011 indicated that the gold mineralization extended further southeast from the Mary zone to the adjacent Mary LC zone, encompassing a strike length of 780 metres. Subsequent work determined that the Drinkwater, Mary and Mary LC zones were not isolated deposits but represented one continuous zone of mineralization.
Drilling in 2012 and 2013 was designed to support modification of the original Mary pit design to the southwest to include the continuation of mineralization into the Mary LC zone. A highly successful program led to completion of a mineral reserve and resource estimate for the Mary - Mary LC and incorporation of the expanded pit design into the updated LOM Plan. Pre-stripping of the Mary LC pit commenced in the first quarter of 2014 and extraction of development ore was realized in the second quarter of 2014. Attaining commercial production status at Mary LC is expected in Q4 2015.
Infill and step-out drilling on the Mary LC post the March 31, 2014 cut-off date of the LOM Plan has focused on increasing the total mineral resources, upgrading resource categories, lowering the strip ratio and potentially increasing the mineral reserve estimate for the deposit.
Exploration drilling in 2015 has continued to test an area extending up to 250 meters northeast of the Mary LC pit outline. In this northeastern direction, significant mineralization has been intersected at vertical depths ranging from 50 to 150 meters, with depth to mineralization generally increasing to the northeast. Follow-up drilling is under consideration to further investigate this area as a potential open pit and/or underground mining target.
Mary LC Drill Plan
(PDF 2.2 Mb)
The satellite Brodie, Bluelite, Solberry, Wedge and Oromonte deposits are situated west and southwest of the Drinkwater pit and lie in close proximity to the leach pad. These deposits are part of a semi-continuous trend of mineralization within a shallow-dipping stratigraphic horizon. They lie on the western flank of an anticlinal fold structure and are considered to be related to mineralization within the Drinkwater-Mary trend, which lies on the eastern flank.
An unpdated LOM incorporating the Drinkwater, Mary LC and satellite deposits was reported in the Company's July 21, 2014
news release. The cut-off date for the LOM study was March 31, 2014. Continued drilling on the satellite deposits post this cut-off date is designed to potentially upgrade and increase the reported mineral reserve and resource estimate and potentially extend life of mine.
Brodie & Bluelite Deposits
The Brodie and Bluelite deposits are located 975 metres (3,200 feet) and 1,100 metres (3,600 feet) southwest, respectively, of the Drinkwater pit. Previous operators thought the Brodie and Bluelite deposits were separate mineralized bodies; however, results of Scorpio Gold's drilling has demonstrated they are one semi-continuous zone. The mineralized corridor encompasses a strike length of some 1,370 metres (4,500 feet) and is situated immediately adjacent to the leach pad.
Brodie and Bluelite have been incorporated into the updated LOM (see Mineral Reserve & Resource Estimates
). Drilling has continued on both deposits as well the mineralized structural corridor that trends between, known as the NW Brodie trend. Results to date are expected to positively impact the current resource base for the Brodie and Bluelite deposits and potentially allow for defining a new resource in the NW Brodie trend area.
Brodie Drill Plan
(PDF 1.7 Mb)
Bluelite Drill Plan
(PDF 1.0 Mb)
NW Brodie Trend Drill Plan
(PDF 2.2 Mb)
The Solberry deposit lies west of the Drinkwater pit and 600 meters (1,970 feet) northwest of the leach pad. Solberry has been incorporated into the updated LOM (see Mineral Reserve & Resource Estimates
). Results from expansion drilling in 2014-15 at Solberry are expected to positively impact the current resource base and will potentially allow for defining new resources in the wide area of mineralization that extends +150 meters to the east of the current pit outline and +125 meters south toward the Bluelite deposit.
Solberry Drill Plan
(PDF 1.5 Mb)
The Wedge deposit is located 225 metres (740 feet) southwest of the Drinkwater pit and immediately adjacent to the leach pad. Wedge has been incorporated into the updated LOM (see Mineral Reserve & Resource Estimates
). Results from the expansion drilling program post the March 31, 2014 cut-off date for the LOM study are very encouraging and are expected to positively impact the current resource base for this deposit.
Wedge Drill Plan
(PDF 1.5 Mb)
Oromonte continues to be the least explored of the satellite deposits at Mineral Ridge. It lies within a sparsely drilled target area of approximately 300 x 500 meters that is situated between the Solberry and Wedge deposits. A small mineral resource estimate for the deposit based on 53 RC drill holes has been reported (see Mineral Reserve & Resource Estimates
), but currently there is no economic pit shell developed for Oromonte.
A preliminary interpretation of the mineralization in the Oromonte target area is that it represents a continuation of the mineralized horizon(s) between the Solberry and Wedge deposits offset by normal faulting. A higher-grade zone of mineralization has been intersected in several drill holes over an area of approximately 75 x 85 meters at vertical depths ranging from 85 to 126 meters, which is below the current extent of the estimated resource. It is believed that the occurrence of this higher-grade mineralization at depth may be related to a synform axis which concentrated mineralization in the Oromonte area. This mineralized zone was subsequently down-dropped by late stage normal faulting. A generalized geological model of the mineralization is presented in the Oromonte Cross Section below.
Although not accessible by open pit mining, this deeper zone may be amenable to underground extraction should further results support underground development. Historical underground workings occur in the Wedge deposit area approximately 180 meters to the east.
Oromonte Drill Plan
(PDF 1.7 Mb)
Oromonte Cross Section
(PDF 350 Kb)
Bluelite North Target
The Bluelite North target lies 300-500 meters northwest of the Bluelite deposit and 100-300 meters west of the Solberry deposit. Scorpio Gold's initial phase of widely-spaced exploration drilling in the area intersected significant mineralization in 50% of the holes drilled with several holes reporting mineralization at shallow depths (see July 7, 2015
news release. Scorpio Gold considers Bluelite North a promising exploration target and plans to follow up with additional drill testing in 2015.
The Physik target is situated approximately 300 meters southwest of the producing Mary LC pit. This is an entirely new target area on the Mineral Ridge property discovered by Scorpio Gold's exploration team using a combination of remote sensing, geophysics and structural interpretation.
Initial drill testing of the Physik target over a 200 meter strike length has intersected significant mineralization in 7 of 9 holes, with drill hole MR141107 returning 31.79 g/t gold over 4.57 meters within 15 meters of surface (see November 3, 2014
The mineralization is interpreted to lie along a northwest trend, which is the predominant structural trend common to all of the significant deposits on the property. The results from this early stage of drilling are considered to be highly encouraging. Follow-up drilling is planned in 2015 to determine if there is potential to define a mineral resource in this area.
The Chieftan target is located 500 meters west-northwest of the Drinkwater pit. First pass drilling returned significant results in 10 of 12 holes drilled. No follow-up drilling is currently planned at Chieftan but may be considered at a future date.
Northwest Drinkwater Target
Drilling on the NW Drinkwater target has outlined a mineralized trend extending approximately 300 meters northwest of the Drinkwater deposit. No follow-up drilling is currently planned on this target but may be considered at a future date.
Geology & Mineralization
The Mineral Ridge gold deposits are located on the northeast flank of the Silver Peak Mountain Range. This range lies in the southern reaches of the Great Basin, within the Walker Lane structural corridor. Walker Lane is a 100-km-wide region of right lateral, wrench-faulting which separates the Sierra Nevada batholith to the west and southwest and the Great Basin to the east and northeast.
Mineral Ridge is an anticlinal dome found on the eastern flank of the Silver Peak Range. It has been interpreted as an uplifted metamorphic core complex where unmetamorphosed and unfolded Cambrian strata are in detachment-fault contact with underlying deformed granitoids and Precambrian metamorphic rocks of the core complex. Auriferous quartz lenses of the central gold-quartz district are concordant with foliation in the metasedimentary host rocks of the Precambrian Wyman Formation. Transitional contacts were observed between quartz and alaskite (commonly pegmatitic), and between alaskite and peraluminous two-mica granite, strongly suggesting that the alaskite, quartz, and ore metals were derived hydrothermally from residual granite melt and aqueous fluids.
The property is located on a typical "Nevada Structural System" which is known to control gold mineralization.
To date, seven well-defined gold bearing structures have been documented on the property as follows:
- The North-Northeast Eagles Nest Fault
- The North-Northeast Coyote Fault
- The Northwest BW Normal Fault
- The North-Northwest Gillian Fault
- The Northeast Mary/Drinkwater Cross Fault
- The North-Northwest Mary/Drinkwater Cross Fault
- The North-Northwest Black Warrior Intersection Fault
The known mineralized zones occur over an area of approximately 4,300 m (14,000 ft) north-south and 4,600 m (15,000 ft) east-west. Individual zones can be as much as 43 m (140 ft) thick, usually consisting of a higher-grade 1.5 to 9.0 m wide halo surrounded by a lower-grade mineralized envelope. Two or more high-grade zones are commonly observed stacked on one another. Gold deposition is structurally controlled, and some of the highest grade material is found in mineralization shoots that are at an oblique angle to the direction of movement of the upper plate slab.
Gold is present as native gold and electrum, and generally occurs as rounded, angular, irregularly shaped and elongated inclusions and intergrowths in quartz, frequently associated with micaceous minerals or carbonates occupying interspatial spaces or fracture filling. Gold is also frequently associated with goethite, sometimes with relict pyrite, and on occasions intergrown with sphalerite, galena, anglesite/cerrusite and pyrite.
Mineral Reserve & Resource Estimates
On July 21, 2014, the Company reported on an updated Life of Mine Plan ("LOM") completed for the Drinkwater, Mary/LC, Brodie, Bluelite, Solberry, Wedge and Oromonte deposits.
The updated mine plan, which includes an updated mineral reserve estimate, projects mine life for Mineral Ridge extending into the 3rd quarter of 2016, or approximately 29 months as of the end of March 2014, the date of the LOM update. Average ore production over this time frame is estimated at 73,700 tons per month ("t/m") based on estimated Probable Mineral Reserves of 2.1 million tons ("Mt") grading 0.061 oz/ton gold (131,190 oz contained gold) within estimated Indicated Mineral Resources of 2.7 Mt grading 0.059 ounces per ton ("oz/ton") gold (160,300 oz contained gold). Expansion and infill drilling of the satellite deposits has continued since the March 31, 2014 cut-off date for the LOM and is expected to add to the resource base and potentially support further conversion of current mineral resources to mineral reserves.
This LOM is inclusive of the Drinkwater and Mary/LC deposits and the five satellite deposits, Brodie, Wedge, Bluelite, Solberry and Oromonte. An Inferred Mineral Resource estimate for the Brodie, Wedge, Bluelite, and Solberry deposits, dated June 1, 2013, was reported in the Company's August 16, 2013 news release. Development drilling over the past two years has allowed for an upgrade of the previous resource estimate to include Indicated Mineral Resources containing Probable Mineral Reserves. The updated Indicated Mineral Resource estimate for the five satellite deposits is 625,100 tons grading 0.061 oz/ton gold (38,360 oz contained gold), which includes a Probable Mineral Reserve for four of the deposits of 463,880 tons grading 0.065 oz/ton gold (30,050 oz contained gold).
Principal Outcomes - Life of Mine Study
- Estimated Probable Mineral Reserves: 2.1 Mt grading 0.061 oz/ton gold (131,190 oz contained gold).
- 2.5 year mine life at 73,700 t/m ore throughput as of March 31, 2014.
- Total gold production over projected life of mine is approximately 97,700 ounces gold which includes 85,300 recoverable ounces mined and 12,400 recoverable ounces gold in inventory as of March 31, 2014.
- Average total cash cost per ounce of gold sold of $1,074.
- After tax net present value until mine closure of $7.4 million (8% discount rate) using an average gold price of $1,300/oz.
- Key risks include:
- Current estimated reserves may not be realized causing a shortfall in gold production.
- Current water requirements for the heap leach solution would be in jeopardy if the main water well were to fail. The Company is currently rehabilitating a second water well to reduce this risk.
- Key opportunities include:
- Current estimated reserves may be exceeded, thus increasing gold production.
- There is potential to identify additional mineralization from drill-defined extensions to the known deposits, which may support Mineral Resource estimation updates and potentially be converted into Mineral Reserves.
- Exploration potential of other identified prospects on the Mineral Ridge property.
Mineral Reserves presented in Table 1 have demonstrated economic viability. All Mineral Reserves are classified as Probable Mineral Reserves with no Proven Mineral Reserves.
Table 1. Probable Mineral Reserves Estimate - March 31, 2014
Notes to Table 1:
Gold Grade (oz/ton)
Contained Gold (oz)
Strip Ratio (waste:ore)
Table 2. Indicated Mineral Resources Estimate - March 31, 2014
- The effective date of the Mineral Reserve estimate is March 31, 2014.
- The Mineral Reserve estimate was prepared by Jim Ashton, P.E., of Scorpio Gold and audited by independent qualified person, Randy Martin, SME-RM, of Welsh Hagen Associates.
- Mineral Reserves are reported at a 0.020 oz/ton gold cut-off grade.
- Mineral Reserves are contained within a designed pit with access ramps based on the Lerchs-Grossmann (LG) algorithm utilizing a $1,300 oz gold price. The optimization mining cost was $4.15/t of ore mined at Drinkwater, $3.79/t of ore mined at Mary/LC, $2.96/t of ore mined from the satellite deposits, $2.92/t for waste mined from the Drinkwater, $2.57/t for waste mined from the Mary/LC and satellite deposits, and $1.56/t of fill mined. An average processing cost of $11.29 was applied per ton processed. G&A costs were applied at $4.70 per ton processed. Shipping and refining costs of $28.82/oz gold produced were applied. A 65% metallurgical recovery was applied. Overall pit slope angles ranged from 45 degrees to 49 degrees.
- No economic pit was developed for the Oromonte deposit.
Table 3. Inferred Mineral Resources Estimate - March 31, 2014
Gold Grade (oz/ton)
Contained Gold (oz)
Notes to Tables 2 & 3:
Gold Grade (oz/ton)
Contained Gold (oz)
- Mineral Resources in Table 2 are reported inclusive of Mineral Reserves.
- The effective date of the Mineral Resource estimate is March 31, 2014.
- The Mineral Resource estimate was prepared by Jim Ashton, P.E., of Scorpio Gold and audited by independent qualified person, Randy Martin, SME-RM, of Welsh Hagen Associates.
- Mineral Resources are reported at or above a 0.020 oz/ton gold cut-off grade.
- Mineral Resources are reported using a long-term gold price of US$1,500/oz.
- Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
The Mineral Resource estimate is based on a total of 2,514 drill holes and 108,969 assay results collected between 1939 and 2014 from the Drinkwater, Mary, Brodie, Bluelite, Solberry, Wedge, and Oromonte deposits. The cut-off date for information used in the geologic model and Mineral Resource model was March 31, 2014.
Key Assumptions, Parameters & Methods Used:
- Mineral Resources reported are constrained within a conceptual Lerchs-Grossmann (LG) pit shell and are inclusive of Mineral Reserves.
- The economic parameters used to construct the Mineral Resource LG pit are the same as those used in the Mineral Reserve pit except that the price of gold was increased from $1,300 per ounce to a long-term gold price of $1,500 per ounce.
- The block model consists of 15 ft x 15 ft x 10 ft blocks estimated using inverse-distance to the second power methodology. Mineralized envelopes were constructed on 25 ft spaced sections using a 0.010 oz/ton gold assay grade as a guide. The envelopes were combined into wire-frames that defined the extent of mineralization for all the deposits.
- Extensive historical underground workings are present in the Drinkwater and Mary areas. Underground wire-frames were used to remove the percentage of the block contained within the mineralized envelope.
- A single bulk density factor of 13 cubic ft per short ton was assigned to all blocks that represent in-situ rock and used in the Mineral Resource estimates.
- In the Drinkwater area, assays were capped at a threshold of 1.6 oz/ton gold, in the Mary/LC and Oromonte areas assays were capped at a threshold of 1.0 oz/ton gold, in the Brodie, Bluelite, and Solberry area assays were capped at 0.650 oz/ton gold, and in the Wedge area assays were capped at 1.50 oz/ton.
- Mineralization pinches and swells, and is not easily mapped, and correlation between sections is often difficult, therefore outlier restriction was also applied to restrict gold interpolation at a threshold of 0.5 oz/ton gold and a distance of 60 ft for the Drinkwater and Mary/LC deposits and a distance of 40 ft for the satellite deposits.
The Mineral Resource and Mineral Reserve estimates were prepared by qualified person, Jim Ashton, P.E., of Scorpio Gold and audited by independent qualified person, Mr. Randy Martin, RM-SME of Welsh Hagen Associates. An independent technical report supporting the disclosure of the Mineral Resource and Mineral Reserve estimate and Life of Mine Plan was filed on SEDAR on September 3, 2014 and is also available here: View Technical Report (PDF 27.3 Mb)