Iskut is a district scale property in a broad northwest trending hydrothermal alteration zone spatially associated with regional faults and intrusions.  The area includes the past producing Snip and Johnny Mountain gold mines and the Bronson Slope gold-copper resource. The Property and surrounding areas are underlain by stratified rocks of the Upper Triassic Stuhini Group, Lower Jurassic Hazelton Group and early Jurassic intrusions.  This area is bounded on the southwest by the Sky Fault System, a regional fault system interpreted as a major thrust fault.  Geological architecture at Iskut is nearly identical to the KSM property.

Seabridge’s initial exploration efforts at Iskut evaluated historical gold occurrences and merged these mineral occurrences into a unifying geological model.  That model showed the Iskut property contained the characteristics of high and intermediate sulfidation epithermal systems directly related to gold-copper porphyry hydrothermal systems.  Exploration discovered an untested lithocap, the hydrothermal alteration indicative of buried porphyry systems, at Quartz Rise.  Initial work in the Quartz Rise Lithocap focused on the discovery of a high sulfidation epithermal precious metal deposit, but results showed that the lithocap had been deeply eroded.  Drilling results of the lithocap encountered veined and altered intrusive rocks characteristic of a gold-copper porphyry occurrence. Due to glacial erosion, the source intrusion for the lithocap can be tested from the surface. 

The scientific and technical information in respect of the KSM Project herein was derived from the technical Report entitled KSM (Kerr – Sulphurets – Mitchell) Prefeasibility Study and Preliminary Economic Assessment dated effective August 8, 2022. This information was prepared by leading consulting firms and their Qualified Persons (as defined in NI 43-101), all of who are independent of Seabridge and are listed below along with their areas of responsibility:
(i) Tetra Tech, Inc. under the direction of Hassan Ghaffari P.Eng (surface infrastructure, capital estimate and financial analysis), John Huang P.Eng. (metallurgical testing review, permanent water treatment, mineral process design and operating cost estimation for process, general and administrative (“G&A”) and site services, and overall report preparation)
(ii) Wood Canada Limited, under the direction of Henry Kim P.Geo. (Mineral Resources)
(iii) Moose Mountain Technical Services under the direction of Jim Gray P.Eng. (open pit Mineral Reserves, open pit mining operations, mine capital and mine operating costs, MTT and rail ore conveyance design, tunnel capital costs)
(iv) N. Brazier Associates Inc. under the direction of W.N. Brazier P.Eng. (Electrical power supply, energy recovery plants)
(v) ERM Consultants Canada Ltd. under the direction of Rolf Schmitt P.Geo. (environment and permitting)
(vi) Klohn Crippen Berger Ltd. under the direction of David Willms P.Eng (design of surface water diversions, diversion tunnels, tailing management facility, water treatment dam and RSF and tunnel geotechnical)
(vii) BGC Engineering Inc. under the direction of Derek Kinakin P.Geo., P.L.Eng., P.G. (rock mechanics, geohazards and mining pit slopes)
(viii) WSP Golder Inc., under the direction of Ross Hammett P.Eng (Block Cave mining)