The Rosetta Stone showing is located on Walton Creek, approximately 11.5 kilometres southwest of the community of Hills.
Regionally, the area is underlain by a sequence of Devonian-Mississippian pelitic quartzites and pelites belonging to the Silver Creek Formation and Milford Group, Upper Triassic, Lower Jurassic carbonaceous meta-mudstone with minor calcareous quartzite and limestone belonging to the Slocan Group, and rare volcanic breccia of the Rossland Group. These have been intruded by Jurassic diorite porphyry dikes and sills, Cretaceous granite stocks and dikes, and Tertiary lamprophyre dikes. The area covers a southeast plunging gentle anticline roughly parallel to McDonald Creek and north-south trending faults, of possible Tertiary age, dissect the area.
Locally, a zone of anastomizing, polymictic, smokey-pervasive-drusy-silica textured, pyrite-, sericite-, carbonate-bearing hydrothermal breccias are shown in outcrop. The zone occurs at the contact of an aplitic body and metamorphosed sediment (pelite/schist) and is roughly east-west trending with a steep to vertical dip.
The property was acquired by prospector Tom Kennedy in 2006. Subsequently, the property was optioned to Kootenay Gold Inc., who later optioned it to Theia Resources. Grab samples with high-grade gold from 2006 were verified by further composite sampling of the epithermal breccia in 2007, and the showing was drill tested in 2009. Three mineralized zones have been identified on the property: the Creek zone, Road zone and Skid Trail zone.
On the Creek zone, a strong hydrothermal system with intense clay and anthophyllite alteration accompanied by chalcedonic veining, quartz flooding, crackle breccias and hydrothermal breccias occurs. Fine pyrite accompanies veining, crackle breccias and hydrothermal breccias. The structure has been traced for 50 metres along strike and to a depth of 110 metres. It remains open along strike to the northeast and southwest and at depth where it appears to be wider and more intense. It has a steep apparent dip to the southeast. Surface sampling of selected grab samples have returned up to 21.1 grams per tonne gold and drilling returned 2.75 grams per tonne gold over 1.0 metres in RS09-2 and broader zones of anomalous gold, including 0.71 grams per tonne gold over 8.89 metres in RS09-5 (Assessment Report 31792). In 2010, a program of channel sampling was undertaken on a zone of silicified and brecciated aplitic granite. Twenty-five samples returning multi-gram gold values with the highest grade being 31.8 grams per tonne. The remainder of the samples was all anomalous in gold. The average value of the 38 samples was 4.3 grams per tonne gold (Assessment Report 32087).
The Road zone occurs 590 metres northeast of the Creek zone and consists of sericite- and clay-altered granite with narrow zones of hydrothermal breccia. In 2009, Borehole RS09-9 intersected two sections of anomalous gold. The uppermost section, grading 0.29 gram per tonne gold over 2.33 metres is hosted by a clay chlorite-altered mafic dike with limonitic fractures. The lower section, returning 0.52 gram per tonne gold over 2.34 metres, is hosted by clay/anthophyllite-altered granite with crackle fracturing and chalcedonic veining similar in texture to mineralization and alteration in the Creek zone (Assessment Report 31792).
The Skid Trail zone, containing quartz veining within altered granite, occurs 630 metres north east of the Creek zone and approximately 65 metres south east of the Road showing. In 2009, Hole RS09-11 intersected a lamprophyre dike cut by several narrow chalcedonic veinlets with minor pyrite, returning 0.27 gram per tonne gold over 1.0 metre (Assessment Report 31792).
In 2008, an airborne electromagnetic and magnetometer geophysical survey was conducted for Kootenay Gold Inc., and Theia Resources Ltd. on the property containing the occurrence. Results correlated with orientation and placement of the Ruby Range, Meadow Mountain, and affiliated quartz diorites, and the local sill-mudstone complex (Thompson, R. (2008-12-01): Technical Report on Geology, Exploration Programs and Results from the Rosetta Stone Property with Recommendations for Further Exploration).
Anomalous quartz veins located south of the occurrence were observed to contain pyrite, galena, and sphalerite mineralization, and trend 40 degrees cutting older Devonian and Mississippian pelite and quartzite. This vein system was estimated to be 60 metres wide by greater than 800 metres long (Thompson, R. (2008-12-01): Technical Report on Geology, Exploration Programs and Results from the Rosetta Stone Property with Recommendations for Further Exploration).
