The Gum Creek-Lower Gum (Hodgie) carbonatite occurrence is located in a steep northeast-facing high mountain valley and along the adjacent ridge to the southwest, northwest and its upper southwest-facing slopes, south of Gum Creek and approximately 4.5 kilometres southeast of the creek’s mouth on the North Thompson River. The Fir (MINFILE 083D 035) occurrence is located approximately 3.7 kilometres to the northwest.

Regionally, the area is underlain by Neoproterozoic (Hadrynian) Horsethief Creek Group metasedimentary rocks and derived gneisses. Medium to coarse crystalline sovite and beforsite carbonatite sills intrude the Horsethief Creek rocks. For further information on regional and local geology of the area refer to the nearby Fir (MINFILE 083D 035) occurrence.

Locally, the area is underlain by interlayered metasediments and metabasites of the Proterozoic Horsethief Creek Group. Gneisses in the area have a general strike of 040 degrees with dips of 15 to 20 degrees southeast and are local folded and offset by later faults. The Horsethief Creek Group rocks are intruded by sills of carbonatite and later pegmatitic sills and dikes.

The Gum Creek occurrence was originally described as a 1- to 2-metre thick layer or sill of carbonatite and/or fenite(?) that has been traced along strike for approximately 100 metres. Based on geochemistry and field observations the carbonatite is tentatively classified as being of sovite (calcite-dominated) composition.

Later work (circa 2008) describes the Gum Creek carbonatite as a 15- to 35-centimetre thick calciocarbonate (sovite) interbedded in gneiss with rounded rip-up clasts of fenitized gneiss. Minor magnesiocarbonatite is also reported. Mineralization includes apatite, richterite, calcite and ±magnetite as rounded crystals up to 5 centimetres in size. A sheared pegmatite is reported to cut-off the carbonatite to the south.

The Lower Gum and Hodgie zones are located approximately 900 metres to the southwest of the Gum Creek zone and are centred in the area of the Hodgie (MINFILE 083D 046) vermiculite occurrence.

In 1989, a lone rock sample from the carbonatite is reported to have yielded 0.3211 per cent niobium pentoxide (Nb2O5), 0.0075 per cent tantalum pentoxide (Ta2O5) and 1.82 per cent phosphorus pentoxide (P2O5) with light rare earth elements yielding up to 0.1905 per cent lanthanum and 0.2666 per cent cerium (Assessment Report 26990).

In 2002, a rock sample (10538) assayed 0.2245 per cent niobium and approximately 0.6242 per cent total rare earths (Assessment Report 26990). Values for promethium and scandium were not reported.

Also at this time, a panned concentrate sample (12453H), taken from Gum Creek to the northeast, yielded elevated niobium value of 307 parts per million, whereas two other pan concentrate samples (12471H and 12360), taken to the west, yielded elevated niobium values of 433 and 410 parts per million, respectively (Assessment Report 27131).

In 2005, samples of carbonatite from the Gum Creek area yielded values of up to 182 parts per million tantalum pentoxide (Ta2O5), 0.34 per cent niobium pentoxide (Nb2O5) and 3.38 per cent phosphorus pentoxide (P2O5; Assessment Report 29024).

In 2006, eight outcrop grab samples (24538 through 24545) of sovite carbonatite from the Gum Creek area yielded an average of approximately 3751 parts per million total rare earth elements with 1259 parts per million niobium, with maximum values of approximately 5222 parts per million total rare earth elements and 2407 parts per million niobium (Assessment Report 29024). Values for promethium and scandium were not reported.

In 2008, rock samples from the Gum Creek carbonatite are reported to have yielded values up to 45.0 parts per million tantalum and 2478.5 parts per million niobium with an average of 622.0 parts per million niobium (Assessment Report 31174).

Also at this time, 10 diamond drill holes, totalling 2070.5 metres, were completed on the Lower Gum/Hodgie zone. Holes HO-08-01, -02, -03 and -10 intersected several zones of altered amphibolites yielding up to 1 per cent total rare earth elements (Assessment Report 31174).

Work History

The area has been explored in conjunction with the nearby Paradise (MINFILE 083D 006), Verity (MINFILE 083D 005) and Fir (MINFILE 083D 035) occurrences and complete regional exploration histories can be found there.

During 2001 through 2013, Commerce Resources Corp. completed programs of geological mapping, geochemical (rock, silt and soil) sampling and a 2439.0 line-kilometre airborne magnetic and radiometric survey on the area as a part of the Blue River property.

In 2024, Capacitor Metals Corp. conducted a program of historical data compilation and interpretation on the area as a part of the regionally extensive Blue River Property.