The Monitor mine is located on the north shore of the Alberni canal, just at the entrance. The mineralized zones extend back from the shore several hundreds of metres. The property was discovered in 1898 and during 1900 and 1901 steadily produced ore. The mine was reconditioned in 1916 and produced ore again from then until 1918.
The orebodies are found at three points and known as the Maynard, Hedley and Leonard showings. The Maynard is about 600 metres from the canal and is where development occurred from 1900 to 1902. The Hedley is about 300 metres from the canal and was partly developed after it was discouvered in 1910, with development occurring in 1916. The Leonard orebody, located about 500 metres southeast of the Hedley showing and at a lower elevation, was developed after its discovery in 1916.
This skarn deposit occurs in a bed of limestone, probably related to the Upper Triassic Quatsino Formation (Vancouver Group), interbedded with mafic basalts of the Upper Triassic Karmutsen Formation (Vancouver Group). The bedding strikes 115 degrees and dips 20 degrees to the southwest. These rocks are bounded on the east by a large body of granodiorite of the Early to Middle Jurassic Island Plutonic Suite (formerly the Island Intrusions). The rocks are intruded by a body of granodiorite porphyry, probably a dyke, lying west of the deposits and striking in a northerly direction.
The ore consists of pyrrhotite and chalcopyrite with small amounts of magnetite and pyrite. It occurs chiefly in the altered limestone, which consists of calcite, quartz, garnet, epidote and actinolite. Some ore is found in the metamorphosed volcanic rocks which are altered to epidote, chlorite and hematite. The strike of the Leonard orebody is reported to conform with the country rock outside the portal of the adit. An average sample taken from a crosscut in the adit across 0.6 metres assayed 6.1 per cent copper, 17.14 grams per tonne silver and a trace of gold (Minister of Mines Annual Report 1919, page 253).
For the six years that the Monitor mine was in production, a total of 1,288 tonnes was mined, producing 37,137 grams of silver, 62 grams of gold and 116,946 kilograms of copper.
In 1986 through 1989, Chelan Resources completed programs of geochemical sampling, geological mapping and ground geophysical surveys on the area as the Liquid Sunshine project.
In 2007 through 2013, Nahminto Resources completed a program of prospecting, geological mapping, geochemical sampling, a ground magnetometer survey and airborne geophysical surveys on the area as the TJM claims, apart of the Nahmint property. In 2008, two grab samples, 362676 and 362677, of oxidized skarn from a former trench assayed 0.68 and 5.0 per cent copper, 3.7 and 0.13 per cent zinc with 12 and 23 grams per tonne silver, respectively (Assessment Report 29660). In 2009, a select grab sample (2009012) from a 0.2 metre thick exposure of skarn in the shaft assayed 3.41 per cent copper, 0.223 per cent lead, 58.2 grams per tonne silver and greater than 1 per cent zinc. Another sample (200914), taken approximately 100 metres to the east of the shaft, from a 0.2 metre thick exposure of pyritic quartz containing chlorite, jarosite, chalcopyrite and hematite assayed 1.02 per cent copper, 45.6 grams per tonne silver and greater than 1 per cent lead and zinc (Assessment Report 31248).
