The Cedar (G Zone) area is underlain by Helikian Aldridge Formation (Purcell Supergroup) quartzite, argillaceous quartzite, and argillite.

At the Cedar showing (G Zone), a strong shear zone crosscuts nearly flat-lying argillites and argillaceous quartzite. The zone is 3 to 5 metres wide and has been exposed in trenches over a strike length of about 1100 metres. The shear gouge is grey to buff colored, oxidized (limonite?) and carries angular fragments of the wallrocks. At the showing, the zone is 4.9 metres wide and hosts a massive vein (pod?) of galena which assayed high values in lead and silver.

In 1982, it was reported that 6 diamond-drill holes put down in 1979 and 1980 on the Cedar 8 and 10 claims of the R.H. Stanfield property. The 6 holes totalling 5997 metres (1-79, 2-79, 3-79, 4-79, 5-79 and 2-80) were completed on the Cedar 8 and 10 claims (Assessment Report 10304). Holes 4 and 5 were located near the access road up #4 Mountain and the adit tunnel on the G zone and holes 1, 2 and 3 were located a short distance up Little Sand Creek on a branch road. The 6 drill holes were thought to have penetrated upper and probably middle Aldridge strata. All rock types were reported to contain disseminations, fracture fillings, very thin strata stringers, quartz veins and quartz siderite veins carrying pyrite and pyrrhotite along with minor chalcopyrite and limited blebs of galena. The mineralization was examined megascopically but no sections were taken for sampling.

In 1988, two rotary-drill holes totalling 110.5 metres were completed on the Cedar 8 Claim for R.H. Stanfield (Assessment Report 17850). The high-grade silver-lead G zone (082GSW054) is located on the northeast area of the Cedar 8 claim. Highgrade silver lead mineralization was exposed at the northeast area of the Cedar 8 claim. A 12-metre adit tunnel was driven easterly on a fissure zone 3 to 5 metres wide. An adit tunnel was located 6 metres north in more stable ground and directed nearly parallel to the mineralized zone for 30 metres. It was then directed 30 metres back to penetrate the mineralized zone. One flat hole was diamond drilled southerly underground 12 metres from the face of the tunnel to check the width and grade of the mineralized zone. In order to check the geology of the area east of the showings, holes CB-G2-88 and CB-G3-88 were drilled with rotary drill equipment to depths of 61.8 and 48.7 metres. Sheared and altered Aldridge argillaceous quartzite was penetrated in both of these vertical holes. Quartz stringers and quartz siderite fracture fillings contain pyrite and pyrrhotite and some chalcopyrite and galena.

In 1988, 10 drill Holes (C3-88, C8-G-1-88, D1-1-88, D2-2-88, D10-1, D10-2, D10-PP1, D10-PP2) totalling 544.8 metres, were completed on the Cedar 1A, Cedar 3A, Dogwood 1A, and Dogwood 4 Groups for R.H. Stanfield (Assessment Report 19034). A vertical rotary hole was drilled on the Cedar 3 claim in 1988 and one hole was drilled on the Cedar 8 claim in 1988, at or near the G zone. Four rotary holes were drilled on the Dogwood 12 claim in 1988 and 4 holes were drilled on the Dogwood 10 claim in 1988. Road work and erosion control was completed over the Dogwood 9 and 11 claims and the Cedar 1,3 and 5 claims in 1988 and 1989. Only hole (C8-G-1-88) reached bedrock.

In 1997 and 1998, 335 metre of adit rehabilitation work and an unknown amount of underground diamond drilling was completed (Assessment Report 25129). In 1996 and 1997, one diamond-drill hole totaling 667.3 metres and 2 percussion-holes total 373.4 metres (C8-1-96/97 and C8-2-96/97) were completed for R.H. Stanfield on the Cedar 7 claim (Assessment Report 25129). These two drill holes are located on the magnetic high indicated by the 1982 and 1992 airborne survey (Assessment Report 25129). It was reported that drilling the magnetic anomaly did not reveal any distinct evidence for the cause and extending the holes to greater depth was recommended. In 1998, diamond-drill hole C8-1-96/97 was extended 700.4 metres to final length of 1425.2 metres (Assessment Report 25637). No new evidence explaining the magnetic high was found.

In 2018, a soil sampling program (258 samples collected) was undertaken on the Don and G Zone/Cedar claims (082GSW054) of the Bull River Mine property held by Purcell Basin Minerals (Assessment Report 37660). The analytical results obtained from the 2018 soil samples confirmed and enhanced the large zinc-silver-manganese-copper soil anomaly that is about 1300 metres long and 500 metres wide. The anomalous copper values from the 2018 samples extended the anomaly over 100 meters to the northeast where it remains open.

In 2018, geological mapping and sampling of the Rex (possibly 082GSW018 or 047) and G zones claims occurred, including 36 hectares of drone imaging, 9.6 line-kilometres of ground-based magnetic orientation survey on the Rex Claims and 3.2 line-kilometres of soil sampling on the Murray Lake Claims (Assessment Report 37983). Work completed at the G Zone (Cedar, 082GSW054), including mapping in the G Zone adit, did not yield any results of economic significance. Two field days spent completing geologic and geochemical surveys in the Murray Lake area also failed to return results of significance. The geophysics survey completed on the Rex zone highlighted a trend of high magnetic response which coincided in part with the mineralized vein.

In 2019, drilling was completed by Braveheart Resources Inc. on their Bull River Mine property (Mineral claims 1048930 and 1048988), on exploration targets referred to as the G Zone (082GSW054) and Rex Zone (082GSW047) (Assessment Report 39163). Six NQ2 diamond-drill holes were completed on the upper G Zone from 2 drill pads totaling 501.02 metres. Only one hole (GZ-19-04) definitively intersected the target structure. The zone was intersected at 33.4 metres downhole for approximately 10 centimetres. The vein consisted of solid sulphide, mostly galena with some brown sphalerite and minor pyrite. Despite intersecting the targeted structure in hole GZ-19-04, the results could not be duplicated in the other drillholes. A 0.10-metre drill length graded 669 grams per tonne silver, 10 per cent lead, and 1.74 per cent zinc (Assessment Report 39163). Despite intersecting the targeted structure in hole GZ-19-04, the results could not be duplicated in the other drillholes, and a definitive orientation of the structure could not be determined, indicating that the structure may be presented in discontinuous pods.