The Strap is a minor fluorite showing, situated in the Tee 126 claim, halfway between Teeter Creek and Mount Halkett, 19 kilometres north of the settlement of Liard River on the Alaska Highway (Assessment Report 3975, Maps 5, 23). It is part of one of the most important areas of fluorite mineralization in British Columbia.

The region is underlain by Lower to Upper Paleozoic, platformal sedimentary rocks of Ancestral North America (Geological Survey of Canada Maps 46-1962, 1712A, 1713A). The Strap showing is one of many similar fluorite deposits in a 17-kilometre long belt extending north from Liard Hot Springs Provincial Park. All the deposits in the belt occur at or just above or below the unconformity between the Middle Devonian Dunedin Formation and the Upper Devonian Besa River Formation. The Strap is in the far north of the fluorite belt.

The Dunedin Formation consists of mid- to dark grey, massive to thinly-bedded fossiliferous limestone. It is generally exposed in the Teeter and Mould creek valleys, which are characterized by karst and 'mesa and butte' topography. The overlying Besa River Formation is predominantly black shale or slate and argillite, with some calcareous shale and minor, buff-brown dolomitic layers. The unconformity between the units is generally marked by brecciation and is very irregular in detail, probably due to an erosional or disconformable relationship between them, or to later faulting along the contact (Assessment Report 3975). The mineral deposits in the Liard fluorite belt generally occur as lenticular replacement bodies or infillings in breccias in one or both units.

Most of the Strap showing area is underlain by subhorizontal, unmineralized Dunedin limestone. One small outcrop of shale indicates that the limestone is close to the contact with the Besa River Formation. The other common indicator of the unconformity, limestone or shale breccia, does not appear to be present.

Mineralization is restricted to a narrow zone, intermittently exposed for a length of 180 metres and a width of 12 metres. It consists of a replacement assemblage of fluorite, barite and lesser witherite and barytocalcite. A chip panel sample, taken over one zone measuring 7.5 by 6 metres, assayed 28.6 per cent CaF2 (Assessment Report 3975, Map 23). Another limestone outcrop contains patches of minor fluorite. Elsewhere, an exposure, 12 metres long, consists of massive limonite and goethite.

The full extent and depth of the mineralization are not known, but present indications are that neither is very significant.

Fission-track studies of fluorite from the Gem prospect 15 kilometres to the south suggest that the age of the mineralization is Mississippian (Open File 1992-16).

See the Gem (MINFILE 094B 002) occurrence for a completed work and exploration history of the area.