Vancouver Island

A Mineral Collector’s Paradise

By James Laird, Laird Exploration Ltd.
Copyright 2003

Vancouver Island, perhaps better described as “Treasure Island”, hosts an astounding variety of rich mineral deposits. Nearly every kind of metal deposit occurs here, from the phenomenally rich gold veins of Zeballos, to the huge polymetallic volcanogenic massive sulphide deposits at Boliden’s Myra Falls operation, and numerous large skarn-hosted iron-copper deposits. Much of my working career as a prospector has been spent seeking gold deposits on Vancouver Island, and I know many more remain to be found.

As I often work on the less-populated northern end of the Island, I am familiar with the mines and other interesting sites found here. This article is not meant to be a complete tour of these mines, rather just highlighting a few interesting and easily accessible areas near the Island Highway. The local rock clubs probably know all these areas well, but people new to the area should probably buy a Backroad Mapbook, Volume II, and study the BC Energy and Mines website for maps and Minfile data of the areas you plan to visit. Rick Hudson’s Field Guide to Vancouver Island mineral sites would also be a very useful asset to have.

As most of the area is well-serviced by logging roads, you can find your way to many interesting localities with just a two-wheel drive vehicle. Two words of caution, good tires and a real spare are a must due to sharp rocks turned up during frequent road grading, and little else is quite as frightening as a entering a sharp corner and being confronted with a fully-loaded off-highway logging truck bearing down on you, so be aware always and drive with your lights on!

Most visitors to the North Island use the Nanaimo ferry, so we will start our trip from this point. Much of the Nanaimo area and adjoining harbour is underlain by Cretaceous coal-bearing rocks mined extensively in the past, one of the main reasons the city was built here. Few good rock exposures are left due to urban growth, but the shoreline should offer better outcrops where accessible. As we travel up the Island Highway from Nanaimo, we pass through many different rock types, so perhaps a little geological background is in order.

Vancouver Island is built on a thick platform of Paleozoic volcanic-sedimentary rocks known as the Sicker Group. Many of you are already familiar with these rocks because they host all of the known rhodonite deposits, and the large polymetallic volcanogenic deposits mined at Myra Falls near Buttle Lake and several other former mines. I will not dwell on this rock package because it is not well exposed north of Campbell River, although it does trend up the center of the North Island to the vicinity of the settlement of Woss.

Overlying the Sicker Group is the Upper Triassic Karmutsen Formation, a thick (up to 5 km) package of oceanic basaltic rocks. Much of these rocks are just boring dark green lava flows and pillow basalts, but as we reach the top of the section, sedimentation begins in the form of limestone beds in small basins, and the upper parts of the individual flows are often amygdaloidal or feldspar porphyritic. In the amygdaloidal sections, small gas holes and fissures in the lavas have commonly been filled with quartz, epidote, prehnite, pumpellyite, native copper, chalcopyrite, chalcocite, bornite, vanadium minerals, hematite, magnetite, pyrite, and even high-grade gold values. This mineralization occurs syngenetically with the lavas and sediments, and if it is metamorphosed and re-mobilized into younger hydrothermal systems, it can contribute to forming skarn orebodies in the overlying Quatsino Limestone or even gold veins.

Above the Quatsino is the Lower Jurassic Bonanza Volcanics, similar to the Karmutsen but overall a little lighter green in colour and with more explosive breccia rocks and volcanic sediments in the section, which can exceed 1 km in total thickness. Parts of the Bonanza erupted underwater, and part as airfall pyroclastics. Iron in the form of disseminated hematite, pyrite, magnetite and jasper, often with some copper minerals, is locally well developed, as at the huge Island Copper Mine near Port Hardy. The granitic magmas that fed the Bonanza Volcanics continued to rise as large intrusive masses during this time, forming the widespread Island Intrusions. The average Island Intrusion rock is probably a granodiorite, but everything from gabbro to syenite can be found locally. The hot, fluid, mobile masses were very important in the formation of many large mineral deposits on the Island, notably the skarn-type and Island Copper porphyry-type. A unique feature of these rocks is the association of blue dumortierite, and black or green tourmaline with the porphyry copper and some skarn deposits.

The last significant rock-type of note outside of the Cretaceous coal-bearing rocks, is a series of small granitic intrusives of Tertiary age, about 35 million years old. These intrusive bodies, called the Catface Intrusions, were very important in the formation of rich gold-quartz vein deposits. They have a very different metal signature than any of the previously described mineralization, with arsenic minerals often forming part of the vein systems. Some of the better known Tertiary gold deposits are found on Mt. Washington, and at Zeballos. Zeballos gold veins are often amazingly rich and narrow, and have been described at the famous Privateer Mine as being “erratic in grade, between 200 and 300 ounces of gold per ton”. Some of the minerals found in various Tertiary deposits include native gold, tellurides, pyrite, arsenopyrite, chalcopyrite, sphalerite, galena, realgar, cobaltite, and rarely cinnabar and native arsenic.

Now that you know something about the geology and related mineralization systems of Vancouver Island, let’s talk about mineral collecting on the North Island. First, old open pit and underground mines can be very dangerous places to investigate, so at least wear a hard-hat! This will not protect you or your children from large rocks falling from an open-pit wall, or from deadly gasses in an underground mine. Try to collect your specimens from the waste dumps well away from the mine workings. Wear rubber gloves when collecting lead, arsenic or mercury minerals.

Back on the road, the first major collecting area is Mt. Washington near Courtenay. An old copper mine and an unmined gold deposit sit on the northeast side near the top of the mountain, which is mainly composed of highly faulted Karmutsen Formation basalts intruded by a Tertiary stock. On the top of the mountain is a small section of Cretaceous or younger sediments, with rare shell fossils. The copper and gold deposits have formed in a series of flat “detachment faults” and are rich in arsenic minerals such as realgar. Beautiful vuggy crystalline and chalcedonic quartz often forms with the mineralization. Similar mineralization can be found at many places along the local logging roads, and in the vicinity of Wolf Lake closer to Courtenay. Placer gold can be found in Oyster River draining the northern part of the mountain, and oddly enough, visible gold in fine specks is very rarely found in place on Mt. Washington, but it has somehow accumulated in the river and formed relatively large nuggets far downstream.

Just west of Campbell River, the old Quinsam or Argonaut iron mine is a large open pit with good collecting opportunities. The Argonaut is a skarn deposit, mined for it’s magnetite content, but is notable for the abundance of andradite garnet crystals in the orebodies. Also of note is the occurrence of several narrow cobaltite/erythrite-bearing zones within the skarned rocks, although these are probably related to a Tertiary mineralizing event superimposed on the older Mid-Jurassic iron deposits. I have assayed significant gold values in this cobaltite, and I know that visible gold is found in similar deposits elsewhere on the Island.

As we head north from Campbell River towards Sayward, the area is almost entirely underlain by Karmutsen basalts near the top of the section. A unique kind of syngenetic mineral deposit has been found in several locations near Menzies Bay and on Quadra Island, containing copper in the form of chalcocite and native copper, and vanadium in the form of volborthite. Although the known deposits are too small to mine, similar deposits in Alaska have a much greater volume and have made large mines.

Just past Sayward, the Iron Mike mine, a magnetite skarn, is located west of the highway. I do not know the current condition of the roads in the area, but they may be “de-activated” as the Forest Ministry calls it, or ruined as I see it. In the middle of the open pit is a narrow fracture-hosted copper zone having good gold values by assay.

Travelling a short distance north to the Adam River and Eve River drainages, I have seen beautiful quartz and epidote crystals from a little-known location in the area. Perhaps one of the local rock clubs has an exact location, and if you joined up possibly someone could tell you where to look. There are also some small gold-copper deposits along the Adam River, and copper-bearing amygdaloidal lavas. On the highway north of Adam River, a section of Quatsino Limestone is exposed and contains some small karst holes or caves visible from the road.

The next area of collecting interest is in the vicinity of Nimpkish and Bonanza Lakes. Interestingly, Bonanza Lake was not named for mineral deposits but for the immense size of its first-growth trees, now sadly just a memory. The Bonanza area is accessed from near the Zeballos turn-off, and can be driven through to Telegraph Cove and back out to the highway. Along the way, the Bob copper mine, a small open-pit skarn, is located beside the road part way to the main lake. The upper Bonanza River is one of the few designated placer gold rivers on Vancouver Island. The gold source, similar to Mt. Washington, appears to be fine gold coming from Karmutsen lavas at the headwaters, concentrating into small nuggets downstream. Also of note is the white marble quarry near the north end of the lake.

Near Nimpkish River, the Nimpkish Iron Mine is a large open-pit with some collecting opportunities for skarn minerals and magnetite. East of the Island Highway near the small settlement of Nimpkish, the Kinman Creek area hosts a variety of small, rich copper deposits and interesting skarn minerals. Many of the skarn deposits found between here and Noomas Creek to the north, such as my CBL deposit, contain zinc in the form of sphalerite and also host green grossularite-andradite garnet. Several large cave systems are found here too, and local guides are available. Other minerals of note in the local skarns include “peacock” chalcopyrite, magnetite, pyrite, specular hematite, bornite, galena, jasper, diopside, serpentine and more rarely blue dumortierite, lemon-yellow vesuvianite, black tourmaline and pink bustamite.

On the western side of Nimpkish Lake, a visit to the Hustan caves is an easy walk. Near the Kilpala River at the northwest end of the lake, I found a single boulder of Karmutsen amygdaloidal lava filled with a unique mineral, pink clinozoisite. This has resulted in an unusual and attractive green rock with pink spots, which takes a good polish. The original source has not been found as yet.

Driving north on the Island Highway again, lots of Karmutsen and Quatsino rocks are exposed in the road cuts. Your next major stop is at Port McNeill, where all services can be found. West of Port McNeill, the Merry Widow and Old Sport/Coast Copper skarn copper/iron mines can be found on Merry Widow Mountain. The open pits at the Merry Widow Mine are very steep and dangerous with lots of active rock fall, so collecting from the dumps is the way to go. As well, the actual mine area is currently under active development and so is off-limits to the public. The general Merry Widow mountain area north to Alice Lake has many interesting rock outcrops along the main logging road, but watch out for those huge log trucks! Some very large karst or cave systems can be found along the road, such as Devil’s Bath and the Eternal Fountain.

Back on the highway north from Port McNeill, your next major stop is Port Hardy, near the Island Copper open pit mine, now flooded with seawater. Several books and displays at the local museum tell the story, however. Port Hardy is the northern terminus of the Island Highway, but numerous logging roads lead out towards the wild West Coast and access many more mineral deposits and caves similar to those already mentioned. Camp spots are easy to locate along the many lakeshores, but bring good rain gear. I hope you have a great time rockhounding on “Treasure Island”!