The LUMPY showing is a polymetallic quartz vein system located on the north slope of Lightning Peak, approximately 900 metres north-northeast of the summit.
The showing occurs in a bed of coarsely crystalline, grey limestone of the Devonian-Triassic Harper Ranch Group which is hosted by granodiorite and diorite of an unnamed Middle Jurassic intrusion.
The limestone bed is approximately 30 metres wide, strikes northwesterly and dips 60 degrees to the southwest. It is associated with greenstone and granitic intrusives.
Trenches and 2 short adits at the showing expose prominent jointing in the limestone at 60 degrees. This fracture set is filled with thin quartz veinlets containing minor amounts of sphalerite, galena, ruby silver, and traces of native silver and gold. Disseminated pyrite in the limestone has also been noted.
The LUMPY claim was staked in 1918 by J. Prough and W.A. Johnson. Initial development work included a short adit, but the property was eventually abandoned because of poor results. In 1927, the property was re-staked by G. Boug and R. Lee. A 1930 report describes 2 adits, one of which was 9 metres long, the other 21 metres. To the south, on the hillside above the adits, there are a number of open-cuts and trenches.
In 1968-69, International Mine Services Ltd. staked much of the Lightning Peak area and carried out a variety of exploration programs for the Great Horn Mining Syndicate Inc. Most of this work was focused on the WATERLOO (082ENE017) mine, 2.75 kilometres to the northwest. The LUMPY showing was covered by the PEAK 91 claim at this time, however no work in this area was recorded.
In 1980, Zalmac Mines Limited staked the LUMPY showing and in the following year they carried out a geological survey of the old workings. A grab sample of limestone containing specks of galena and sphalerite assayed 162.8 grams per tonne silver, 1.37 per cent lead and 1.07 per cent zinc (Assessment Report 9984). Several of the 21 trenches mapped expose minor shear zones striking 60 degrees. The limestone weathers rusty, suggesting the presence of pyrite, especially near intrusive contacts.
In 1984-85, Zalmac Mines Limited carried out VLF-EM and IP surveys over portions of the BIG P 1, 2 & 3 claims, which include the LUMPY showing. The surveys identified 3 polarizable anomalies coincident with east-west VLF-EM conductors. It was speculated that these anomalies may represent mineralized shear zones. A sinuous, east-west trending conductor passing through the LUMPY area was detected by a 1985 VLF-EM survey. Trenching on this conductor, to the west of the LUMPY showing, was unable to reach bedrock.
In 1988, additional trenching was carried out by Zalmac Mines on their BIG P claim group. Two trenches near the LUMPY showing exposed a pyritic limestone, and minor chalcopyrite was noted on fracture surfaces in trench TR88-1. Several grab samples collected from the adits in 1992 failed to provide encouragement for further work.