A phosphate horizon outcrops on the east slope of Mount Lyne, 11 kilometres southeast of Elkford, and continues southward west of Line Creek for 8 kilometres before crossing the creek.

Regionally, the area is underlain by a series of generally north-trending sedimentary rocks including dolomitic carbonate rocks of the Mississippian Etherington, Mount Head and Livingstone Formations (Rundle Group) and Pennsylvanian to Permian Rocky Mountain Group, fine clastic sedimentary rocks of the Triassic Spray River Group, undivided sedimentary rocks of the Jurassic Fernie Formation and undivided sedimentary rocks of the Jurassic to Cretaceous Kootenay Group.

Locally, a 4.9-metre thick phosphate interval is exposed at Mount Lyne at the base of the Jurassic Fernie Group. The group unconformably overlies siltstone of the Triassic Sulphur Mountain Formation (Spray River Group). The section dips 45 to 70 degrees east throughout its strike length. The base of the phosphate is marked by a 5-centimetre thick marcasite band, and the top is marked by a 10-centimetre thick yellow-orange cherty limestone marker horizon. Within the phosphate interval there are distinct phosphorite and phosphatic shale beds. Shale overlies the phosphate. Phosphorite beds 2 metres thick contain an average of 23.0 per cent P2O5. These beds are overlain by a 0.9-metre thick phosphorite bed containing 13.4 per cent P2O5 (Open File 1987-16, page 73). The phosphorite is composed of moderately well sorted, chestnut brown to dark brown, ovoid phosphate pellets contained in a matrix of quartz, with trace amounts of sericite and illite. Along strike to the south, the phosphate horizon becomes thinner.

Work History

In 2014, an exploration program consisted of reconnaissance prospecting, rock sampling and establishing access to the prospect. Thirteen samples were collected and assayed. Assay results for 2014 sampling of phosphate stockpile samples using a portable Olympus X-Ray Fluorescence (XRF) device were between 24 per cent and 27 per cent P2O5 (Assessment Report 36713).

The 2016 program by Fertoz International Inc consisted of reconnaissance prospecting, rock sampling, and water samples. It was reported that on the Mount Lyne claims, complete sections of the phosphatic strata are 1.11 to 2.1 metres in thickness and average 22.5 per cent P2O5. One incomplete section, where the upper beds were eroded away, was 0.98 metre in thickness and contained 32.62 per cent P2O5. Two rock samples (Assessment Report 36713, Figure 9) were collected near the projected trace of the phosphorite horizon. Assays were conducted by using an XRF Unit. All P2O5 results were low.

In 2018 and 2019, J.T. Shearer conducted minor programs of prospecting and rock sampling on the area as part of the Graves Lake property.

In 2023, Fertox International Organic Inc. conducted a minor program of prospecting and rock sampling on the area as part of the Mt. Lyne Trend property. Float samples containing phosphate, taken approximately 6.3 kilometres to the south, yielded up to 28.69 per cent P2O5 with 0.102 per cent yttrium (sample LC-14-3a; Assessment Report 41378).