The Jericho 18-20 occurrence is located on the west side of Pete’s Creek, a small, north-flowing tributary of Witches Brook and approximately 1 kilometre west of Gump Lake.

The area lies on the eastern flank of the Lower Jurassic Guichon Creek Batholith and is underlain by Chataway and Guichon variety coarse- to medium-grained hornblende-biotite granodiorite that is intruded by Bethlehem phase dike swarms. These rocks have wide compositional and textural ranges, are cut by regional faults, fractures and joints and are locally strongly altered.

Locally, between Pete's Creek and Moly Creek, the granodiorite is intruded by quartz veins and pegmatite and aplite dikes varying in width from 2.5 centimetres to 30.5 metres or greater. Potassium feldspar enrichment is evidently associated with the smaller intrusions. Chalcopyrite with minor molybdenite occurs in very widely spaced joints and fractures trending approximately 025 degrees. Mineralization occurs as thin coatings on the planes of the fractures. The fractures are very tight, vertical and accompanied by a barren conjugate set trending 060 degrees.

In 1966, a 45.36-kilogram sample of this exposure assayed 0.48 per cent copper and 0.009 per cent molybdenum (Assessment Report 922).

Other copper showings are reported to the west on the Jericho 50 claim and to the northwest, along Witches Brook, on the Match 4 and 8 claims and the Jericho 12, 51 and 53 claims.

In 1966, Canadian Superior Exploration Ltd. and Jericho Mines Ltd. completed a program of silt and soil sampling, geological mapping, trenching and a 57.6 line-kilometre induced polarization survey on the area. In 1969, Tremar Mines completed a 50.5 line-kilometre induced polarization survey.