Gold/Copper grades push higher in Seabridge’s Iron Cap drilling

by Keith Powell
View of the KSM Project, near Stewart, B.C.

The KSM Project is one of the largest undeveloped gold projects in the world measured by reserves. — Photo courtesy Seabridge Gold

TORONTO, Nov. 08, 2017 (GLOBE NEWSWIRE) -- Seabridge Gold (TSX:SEA) (NYSE:SA) today reported outstanding results from the final three holes drilled in the 2017 program targeting the plunge projection of the Iron Cap Deposit at its 100%-owned KSM Project in northwestern British Columbia. These holes returned very long runs of some of the highest metal values found to date at KSM.

A total of 10,383 meters of diamond core drilling were completed in 11 holes in this year’s program. All 11 holes returned wide zones of significant grade. The later holes in the program exhibited the best results; the earlier drilling suggested improving gold and copper grades trending to the west and the program was accordingly reoriented in that direction in mid stride. The 2017 program successfully limited the northern and eastern extent of the deposit which remains open down plunge to the west.

Seabridge Chairman and CEO Rudi Fronk noted that “our efforts to expand Iron Cap have proved to be an unqualified success. Going into this year, Iron Cap was clearly subordinate in size to both Mitchell and Kerr in the KSM porphyry cluster. The success of this year’s drilling indicates that Iron Cap is approaching parity in size with these other deposits but with zones of considerably higher metal values. We now see the early development of Iron Cap as a high priority for further study due to its grade, location and size. Revising the project’s mine plan to reflect this thinking would likely have a positive impact on KSM’s projected economics.”

Equivalent grades for gold and copper were calculated using $1275 gold, $3.00 copper and $17 silver. The reported equivalent grade for gold is derived from calculating the revenues for copper and silver for each assay interval at the above noted metal prices, converting the combined copper and silver revenue to a gold grade at $1275 gold, and combining this “equivalent gold grade” with the reported gold grade for that interval. The reported equivalent grade for copper is derived from calculating the revenues for gold and silver for each assay interval at the above noted metal prices, converting the combined gold and silver revenue to a copper grade at $3.00 copper, and combining this “equivalent copper grade” with the reported copper grade for that interval.

Drill holes were oriented using historical information and were designed to intercept the mineralized target down plunge of the strike to the zone as closely as topographic constraints permitted. This orientation will be refined with additional drilling, but current information indicates that the intervals listed above are a reasonable estimate of true thickness of the mineralized zones. For a drill hole plan map and cross-sections please click this link.

Drill hole IC-17-71 was designed as a north and down dip off-set to hole IC-17-70. The hole cut 310 meters of country rock above the Sulphurets Thrust Fault before entering the Iron Cap intrusive complex. Encountered in this hole were several varieties of dioritic porphyry with narrow intervening zones of wall rock. Generally, the upper zone diorite hosts a strong quartz vein stockwork and a phyllic alteration overprint, and is well mineralized with gold and copper. The lower diorite has a weaker stockwork, potassic alteration with magnetite and a high chalopyrite to pyrite ratio. The drill hole was in well mineralized intrusion when completed but it was stopped because it was too far west of supporting data and therefore would not have added further resources from this year’s program. Follow-up drilling will be required to extend the deposit in this area.

The 1,329 meter long drill hole IC-17-72 was sited to test the continuity to the south of high grades encountered in IC-17-70, which had returned 104.6 meters of 1.14 g/T Au and 1.11 % Cu within 925 meters of 0.71 g/T Au and 0.46 % Cu. The high grade intrusion was cut at 424 meters and included an interval of 113 meters with 2.98 g/T Au and 1.56% copper. This is the highest grade combined metal value interval drilled to date at KSM for an intersection greater than 100 meters. Below this interval, a long continuous sequence dominated mainly by the potassic altered diorite also observed in hole 71 continues to the end of the hole.

Drill hole IC-17-73 was designed to fill in a gap between the existing resource and drill holes IC-17-67 and IC-17-72. The Sulphurets Thrust Fault was penetrated at 181 meters.  Below this, mineralization continued to the end of the hole. The Iron Cap zone in this hole is similar to results returned from hole IC-17-66.  Mineralization is hosted by wall rock, intrusion breccia, and diorite porphyry intrusions, with higher grades both up dip and down dip. The hole was terminated before reaching its planned depth due to weather conditions and inability to access the site safely.

Exploration activities by Seabridge at the KSM Project are conducted under the supervision of William E. Threlkeld, Registered Professional Geologist, Senior Vice President of the Company and a Qualified Person as defined by National Instrument 43-101. Mr. Threlkeld has reviewed and approved this news release. An ongoing and rigorous quality control/quality assurance protocol is employed in all Seabridge drilling campaigns. This program includes blank and reference standards; in addition, all copper assays exceeding 0.25% Cu are re-analyzed using ore grade analytical techniques. Random cross-check analyses are conducted at a second external laboratory on at least 10% of the drill samples. Samples are assayed at ISO and ASTM certified laboratories in Vancouver, B.C., using fire assay atomic adsorption methods for gold and ICP methods for other elements.

Seabridge Gold holds a 100% interest in several North American gold resource projects. The Company’s principal assets are the KSM and Iskut properties located near Stewart, British Columbia, Canada and the Courageous Lake gold project located in Canada’s Northwest Territories. For a breakdown of Seabridge’s mineral reserves and resources by project and category please visit the Company’s website at

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