The Herb occurrence is located on the north side of Taylor Arm of Sprout Lake, approximately 3.7 kilometres south east of Mount Porter and at an elevation of about 150 metres.

The area is underlain by a sequence of gently northwest dipping Upper Triassic Karmutsen Formation (Vancouver Group) basalts consisting of intercalated massive and pillowed flows and basalt breccia. Intervolcanic sediments consist of thin (30 to 60 centimetre) lenses of finely crystalline limestone with limited lateral extent. A thinly bedded, laminated chert to siliceous argillite also occurs and is locally fossiliferous at its base. This unit is of limited extent and ranges from 1 to 12 metres in width. Several small irregular masses of diorite possibly related to Jurassic Island Intrusions, intrude this succession. A set of well-developed northwest trending faults and shear zones are typically associated with pyritic quartz-carbonate alteration envelopes.

Locally, at least three showings occur (the A, B and C showings) within 600 metres of one another.

At the A showing, mineralization consists of disseminated chalcopyrite and bornite occurring locally along the rims of pillows or in quartz-calcite filled interstices. A grab sample assayed 9.6 per cent copper and 5.82 grams per tonne silver (Assessment Report 11284).

At the B showing, chalcopyrite occurs on fracture plane surfaces and bed partings in chert and/or siliceous argillite. The chert is fossiliferous at its base where pyrite occurs in thin siliceous lenses and replaces fossils. The chert is strongly fractured and contains numerous quartz stringers some of which contain chalcopyrite. A grab sample assayed 0.33 per cent copper and 10.9 grams per tonne silver (Assessment Report 11284).

At the C showing, an exposure of chert contains malachite within fractures. A sample across a true width of 1.1 metres assayed 1.34 per cent copper and 7.5 grams per tonne silver (Assessment Report 11284).

In 1969, Chilco Dev. completed a program of rock and soil sampling and a ground magnetic survey on the area as the Herb and Moon claims.

In 1970, two diamond drill holes, totalling 45.3 metres, were completed on the Herb 1 claim. These yielded values of 0.19 per cent copper over 6 metres and 0.78 per cent copper over an unknown length as core recovery was poor (Assessment Report 03957).

In 1972, McLeod Copper completed a program of soil sampling, geological mapping and minor drilling. A 2.7 metre drill hole, on the Herb 3 claim, yielded values up to 11 per cent copper. Two diamond drill holes, totalling 11.1 metres, completed on the Herb 16 claim, near the north shore of Sproat Lake, yielded 0.08 and 0.06 per cent copper, respectively (Assessment Report 03957).

In 1974, Rich Mill Mines completed a program of six diamond drill holes, totalling 203 metres. The best intersection was from DH 74-4 (sample 925J) which yielded 1.05 per cent copper and 6.9 grams per tonne silver over 2.1 metres and (Assessment Report 4982). The drill hole was located immediately north of the No.4 Highway in the north eastern corner of the Herb 2 claim.

In 1983, Lear Oil and Gas Corp. completed a program of geological mapping and rock, silt and soil sampling on the area as the Arch claims.