The Howard Creek carbonatite is located at the headwaters of Howard Creek, 13 kilometres east of McNaughton Lake and 41 kilometres northeast of Blue River.

Carbonatites are hosted in a series of Neoproterozoic (Hadrynian) Horsethief Creek Group, Semipelite-Amphibolite division pelitic schists of amphibolite grade (kyanite zone), exposed at approximately 2300 metres in a south-facing cirque. Other lithologies belonging to the Semipelite-Amphibolite division in the area include calc-silicate, pegmatite, granodiorite and marble. At least three phases of structural deformation have been recognized. Multiphase folding and dextral en echelon faulting have displaced all rocks. The regional foliation strikes 090 and dips 40 degrees south. The regional geology is described in detail in the Verity (MINFILE 083D 005) carbonatite occurrence.

At least two separate carbonatite bodies conformable to the regional schistosity have been identified over 300 metres stratigraphic thickness. These outcrops vary from 10 to 20 centimetres thick. Separate bands of sovite and rauhaugite comprise carbonatite outcrops. Infrequent boudins of coarse-grained amphibolite, 5 to 50 centimetres long, are found within carbonatite and nepheline syenite. Dragfolds and tight crenulations are evident in carbonatites, particularly near contacts with the hostrock. This evidence suggests that carbonatites were transposed parallel to the regional foliation during the first deformational event. Other lithologies described at the Howard Creek Carbonatite showing include urtite, ijolite and nepheline syenite (Open File 1987-17).

Minerals identified in the carbonatites include calcite, dolomite, apatite, richterite, hornblende (possibly edenite), clinopyroxene, sphene, biotite, phlogopite, nepheline, zircon, pyrochlore, baddeleyite, ilmenite, magnetite, pyrite, pyrrhotite and plagioclase. Coarse biotite bands, up to 20 centimetres wide, are in contact with nepheline syenite. A nepheline syenite body, approximately 5 by 20 metres in outcrop, appears concordant with the schist/carbonatite complex.

Later work (circa 2008) describes the carbonatite as a primarily calciocarbonatite (sovite) with interlayered fenite and glimmerite, and bands of ultramafic amphibolite containing up to 20 per cent titanite. Blocks of ijolite/urtite in the heavily weathered carbonatite may also represent interlayers. The buff-weathering carbonatite is granular and drapes the ridge. No accurate thickness measurement can be made. Distinctive magnetite and ilmenite crystals up to 20 centimetres are scattered throughout the weathered carbonatite.

In 1984, 18 semiquantitative analyses from the carbonatites and associated rocks yielded 0.25 to 0.50 [MS15.1]per cent strontium with an average content of 0.35 per cent (Fieldwork 1984, p. 99). Some elements from the carbonatites and their quantities, determined by spectrographic methods, are: greater than 2.0 per cent phorphorous, 0.2 per cent strontium, 0.05 per cent barium, 0.04 per cent zirconium, 0.01 per cent chromium, 0.03 per cent lanthanum, 0.03 per cent cerium and 0.03 per cent neodymium; there are also trace amounts of gallium, tin, yttrium, ytterbium and niobium (columbium; Fieldwork 1984). Later chemical analyses of a sovite sample returned the following values: 0.312 per cent strontium, 0.0241 per cent lanthanum, 0.0530 per cent cerium, 0.0223 per cent neodymium and 5.45 per cent phosphorus pentoxide (P2O5; Open File 1987-17, p. 42).

In 2007, 33 grab and chip samples from the occurrence area yielded an average of 12 parts per million tantalum, with values up to 166.9 parts per million, and an average of 89 parts per million niobium, with values up to 566 parts per million (Assessment Report 30011).

In 2009, 14 8.0-metre-long continuous chip samples (72626–72639) down section on the occurrence area yielded an average of approximately 72.7 parts per million niobium, 14.7 parts per million tantalum and 1162 parts per million total rare earth elements (Assessment Report 31948). Values for promethium and scandium were not reported.

Work History

In 1980, Anschutz (Canada) Mining Ltd. conducted a 345.0 line-kilometre airborne magnetic and radiometric survey on the area as part of the Zak and Blue River properties.

During 2007 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.