080121-08MN006-Sabina Hackett River Project Proposal ... - NIRB

Project Descriptionchannelways, interspersed with patchy anthophyllite - cordierite - biotite - garnet - quartz -(sillimanite - sericite). It is contained within a relatively wide envelope of characteristicallyspotted sillimanite - biotite - garnet - quartz - (cordierite - sericite) rock. The less-massive fringesof the massive sulphide lens are enriched in zinc and lead. Silver enrichment occurs in themargins of the lens near surface and copper enrichment occurs in the margins of the massivesulphide lens as well as in the footwall stockwork zone.The Boot Lake zone also occurs within the Mineral Horizon although the latter is thinner in thisarea, with a less complex internal stratigraphy. Sulphides are present in small lenses and incontinuous layers of pyrite, both containing variable amounts of pyrrhotite, sphalerite, galena andchalcopyrite. The East Cleaver zone is a single, fairly homogeneous sulphide body containingpyrite, sphalerite and galena, also situated within the Mineral Horizon. It has been deformedthrough folding and shearing and is now highly contorted, occupying the nose of an overturnedanticline. Both zones are underlain by a stringer zone/alteration pipe.The Hackett River sulphide deposits have associated footwall alteration zones; in particular, theMain Zone has a well-preserved pipe-like feeder zone that is perpendicular to stratigraphy. It isinferred that alteration zone dimensions and orientations approximate their original dimensions.Three alteration types have been identified: spotted rock, main-conduit, and anthophyllitecordierite.Spotted rock is comprised of sillimanite-biotite-garnet-quartz, ± cordierite, ± sericite,and is analogous to chlorite alteration in unmetamorphosed VMS footwall zones. The spots aresillimanite porphyroblasts. Main-conduit alteration (sericite-quartz, ± sillimanite, ± cordierite)and anthophyllite-cordierite alteration (anthophyllite-cordierite-biotite-garnet-quartz, ±sillimanite, ± sericite) are equivalent to quartz-sericite and anthophyllite-cordierite alterationzones in less metamorphosed Archean-age VMS deposits. At Hackett River, anthophyllitecordieritealteration occurs only where hydrothermal alteration has crosscut andesitic strata.Spotted rock locally contains from 2 to 10% combined chalcopyrite, pyrite, pyrrhotite andmagnetite. Main-conduit altered zones and associated quartz veins contain the most significantconcentrations of chalcopyrite, and from 3 to 10% combined sphalerite, pyrrhotite, pyrite andmagnetite. Up to 3% pyrite and minor chalcopyrite occur in the anthophyllite-cordierite-alteredrocks.2.4.2 Mining - GeneralPreliminary economic assessment has identified three deposits: East Cleaver, Main Zone andBoot Lake.The mine design and mine plan for the three deposits are currently at a preliminary level based onlimited mineral resource, geotechnical and hydrological information. During the course of theprefeasibility study alternate mine design options and operating conditions will be examined inorder to optimize the mine design and mine plan.The East Cleaver deposit is located on a topographic high point 1 km to the west of Boot Lake.The Boot Lake deposit is located adjacent to Boot Lake on the eastern slope and extends downbelow the lake at depth. The Main Zone deposit is 2.8 km to the east of the Boot Lake deposit.January 2008 Hackett River Project – Project Proposal Sabina Silver CorporationReport Version B.1 2–10 Rescan Environmental Services Ltd. (Proj. #833-2)