Gold deposits in Ontario are concentrated in a few greenstone belts of the Superior Province, the Archean core of the Canadian Shield that covers most of northern Ontario. The Abitibi belt around Timmins, Kirkland Lake and Detour Lake, the Red Lake belt in the north-west and the Hemlo camp near Lake Superior account for most of the gold the province has ever mined. Southern Ontario had the province’s first gold rush, but its deposits were small.

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Ontario leads Canada. Natural Resources Canada reports that Ontario produced 79.9 tonnes of gold in 2024, 40% of the national total and 3% more than in 2023. The province also led Canadian exploration spending in 2024, according to NRCan’s exploration survey. Most of that money goes into the same belts that have produced for a century, because gold deposits in Ontario tend to cluster, and new ounces are usually found near old ones. Our province-by-province guide to Canada’s gold belts and camps covers the rest of the country.

“Precious metal production in the Kirkland Lake Gold Camp has exceeded 40 million ounces from around 30 mines.” (Ontario Geological Survey)

Where is gold found in Ontario? A map of the main gold belts

If you drew a gold map of Ontario, almost all of the ink would sit north of Lake Superior and Lake Huron. The Superior Province there is made of long, east-west greenstone belts of old volcanic and sedimentary rock separated by granite. Gold deposits in Ontario sit mainly in these belts, in quartz veins and altered shear zones formed late in the belts’ deformation. The Ontario Geological Survey’s mineral inventory records the Dome mine at Timmins as lying in the Abitibi subprovince of the Wawa-Abitibi terrane, of Neoarchean age, and describes the supracrustal rocks of the Red Lake greenstone belt as built over some 270 million years, between 3,000 and 2,730 million years ago. Our guide to gold deposit types and prospecting methods explains the greenstone-hosted style in general terms.

These are geological examples from the Ontario Mineral Inventory and heritage records. They show what each belt has produced. They are not open ground; most of it is held under claims and leases.

How to read an Ontario Mineral Inventory record

The inventory is the single most useful free source on gold deposits in Ontario, and every record follows the same layout. The header gives the record status, for example “past producing mine without reserves or resources”, the primary and secondary commodities, and the location in latitude, longitude and UTM, with the Resident Geologist district. Then come the exploration history, year by year; the geology, down to subprovince, terrane and belt; and two tables that matter most to an investor or a buyer. The reserves and resources table lists each estimate by year, category, tonnes and grade, with the report it came from. The production table lists tonnes milled and ounces produced by year.

Read the references, not just the numbers. Many recent entries cite the Ontario Geological Survey’s own annual open file reports, while older ones cite company reports or handbooks from the 1980s. A figure is only as current as the report behind it.

How does Ontario compare with the rest of Canada? The 2024 regional split from NRCan is below.

Gold mines in Ontario on a map: the tools and the claim rules

Ontario has some of the best public gold data in the world, and all of it can be put on one map. Three government tools matter most.

• The Ontario Mineral Inventory (OMI). A record for every significant occurrence, prospect and mine, with location, geology, history, reserves and production, as used throughout this article.
• OGSEarth and the Geology Ontario portal. Geological maps, geophysics, drill holes and assessment files that companies have filed for work done on claims.
• The Mining Lands Administration System (MLAS). The online claim register. Its map viewer shows active unpatented claims even to users who are not registered.

Putting OMI records and assessment files over the MLAS claim map gives you the best practical Ontario gold mines map there is: every known mine and showing, what has been drilled, and what is held. The gaps between those layers are where claims are still worth registering.

Registering claims and starting early exploration

Claims in Ontario are registered online as cells in MLAS by holders of a prospector’s licence. Before applying for the licence, a person must complete the Mining Act Awareness Program within the previous 60 days. Each cell claim needs assessment work of C$400 per cell per year under O. Reg. 65/18, at the time of writing. Our guide to Canadian claim holding costs in Ontario, Yukon and Newfoundland goes through the numbers.

Most early exploration work beyond basic prospecting then needs an exploration plan or an exploration permit, submitted through MLAS. The province’s exploration plan and permit guide sets out the timing. A plan’s estimated start date should be more than 35 days after submission, and work can begin 30 days after the plan is circulated, unless the holder is told to follow the permit process. A plan is effective for two years. A permit’s start date should be more than 55 days after application, it is posted on the Environmental Registry for 30 days, and the Director decides within 50 days of circulation. Renewals must go in at least 60 days before a permit expires.

Gold in northern Ontario: the Abitibi camps

The Abitibi greenstone belt runs from Timmins east through Kirkland Lake into Quebec, and north to Detour Lake. It is the richest part of the province for gold deposits, and within it three camps show the range of what the belt produces.

Kirkland Lake

The Ontario Mineral Inventory record for the Kirkland Lake camp states that precious metal production there has exceeded 40 million ounces from around 30 mines, most of it from quartz veins associated with the Kirkland Lake Main Break, interpreted as a splay of the Larder Lake–Cadillac break. It is a textbook high-grade vein camp: narrow structures, mined underground for their full depth.

Timmins and the Porcupine camp

At Timmins, the Dome mine record lists J.S. Wilson’s discovery in 1909 and production from 1910 to 2019, with the Blueberry Hill open pit ceasing in 2020. That is more than a century from a single discovery. The Timmins Mine shows how modern reserves are reported: 10.2 million tonnes at 2.82 g/t for 923,500 contained ounces in 2022, according to its inventory record citing the survey’s annual report.

The Timmins Mine’s record is also a good example of how reserves move. It lists 6.46 million tonnes at 3.15 g/t for 654,000 ounces in 2019, 10.9 million tonnes at 2.97 g/t for 1,027,900 ounces in 2021, and 10.2 million tonnes at 2.82 g/t for 923,500 ounces in 2022. Tonnage grew as drilling converted more of the deposit, while grade drifted down. That pattern is common across gold deposits in Ontario’s older camps, where new reserves are added at depth and along strike from the original ore.

Detour Lake

Detour Lake is a different animal. The inventory lists its proven and probable reserves across several years, and the trend is clear in the chart: tonnage has grown by more than half since 2017 as grade has fallen towards three quarters of a gram per tonne. Gold deposits in Ontario do not have to be high-grade to be large; Detour is the bulk-tonnage end of the same belt.

Red Lake and Hemlo: gold in north-western and Superior-shore Ontario

Red Lake

Red Lake, in north-western Ontario, is famous for grade. The Campbell mine’s inventory record notes production of 6,948,736 ounces to 1 January 1990, the pouring of its ten-millionth ounce in 2000, and one sample from the F-Zone, “The Whopper”, estimated to contain 431 troy ounces. After Goldcorp combined the Campbell and Red Lake complexes in 2006, the joint operation produced 507,700 ounces in 2012; Evolution Mining acquired the mines in 2020. The record describes the Red Lake belt’s supracrustal rocks as forming between 3,000 and 2,730 million years ago.

Hemlo

Hemlo is the reminder that Ontario still hides gold in plain sight. The Williams mine record shows claims staked in 1945, trenching that exposed a persistent, strongly sheared zone, and 15 diamond drill holes on the Lake Superior shear zone in 1947. The discovery of the deposit was only announced in August 1982, and the mine began production in December 1985. The record’s annual production table runs from 1985 to 2023; its entries add up to about 12.2 million ounces.

Gold in southern Ontario: Madoc, Eldorado and the Grenville

Gold in southern Ontario has more history than tonnage. According to the provincial heritage plaque at the site, Marcus Herbert Powell, a court clerk and part-time prospector, struck gold in August 1866 on John Richardson’s farm near Madoc. Ontario’s first gold mine went into production there the following year and the community of Eldorado was founded. The Richardson mine was unprofitable and soon closed, but it set off a gold rush to the surrounding region.

The plaque text lists a series of small gold mines established afterwards in south-eastern Ontario: Deloro, Gilmour, Cordova, Feigle, Bannockburn and Golden Fleece. Most were abandoned after a few years because of falling ore values, wasteful recovery methods and a shortage of capital. The rocks here belong to the Grenville Province, younger and more intensely metamorphosed than the northern greenstone belts, and the gold deposits in Ontario’s south have stayed small.

Is it worth exploring for gold in southern Ontario today? The honest answer from the record is that the south has produced far less than the north, and its known deposits were small and short-lived. Explorers who work there tend to look for the same controls that matter elsewhere, shear zones and altered contacts, rather than for the reef systems of the old mines. Compared with the northern belts, gold deposits in Ontario’s south are a niche target.

Placer gold in Ontario and why it is scarce

People who pan in British Columbia or Yukon often ask about placer gold in Ontario. The short answer is that there is little of it worth mining. Ontario was covered by continental ice sheets until geologically recent times. The ice ground up the bedrock, including gold-bearing veins, and spread the debris as till across the landscape, but it has had little time since to be reworked into rich river placers of the kind found in unglaciated parts of the Cordillera.

The result is that gold in Ontario’s rivers is usually fine and scattered. It is similar to what the Alberta Geological Survey found along the North Saskatchewan River, where all the gold was flour gold and few concentrations would have been economic. For explorers, the useful gold in Ontario’s glacial deposits is not a placer to mine but a clue: gold grains in till point back up-ice towards the source. Many of the bedrock gold deposits in Ontario that are still undiscovered will be found that way, under overburden rather than in a creek bed.

Reading till for gold deposits in Ontario

Till sampling is one of the most effective exploration tools in the province. Gold grains, pathfinder elements and indicator minerals from a buried deposit are carried down-ice and form a dispersal train that is larger than the deposit itself. Sampling across the ice direction, counting grains and noting their shape, since freshly released grains are less worn, can lead a programme back to a deposit hidden under swamp and overburden. Our guide to geochemical surveys covers how to plan the sampling grid.

Mineral exploration in Ontario: what works, and where satellites fit

Mineral exploration in Ontario follows a well-worn path, because the belts are well mapped and the data are public. The steps below are how most programmes on gold deposits in Ontario are run, from the first desk study to the first drill hole.

1. Compile. OMI records, assessment files, OGS maps and airborne geophysics over the claim block.
2. Interpret structure. Faults, shear zones, fold hinges and contacts, since the gold follows them.
3. Sample the cover. Till and soil geochemistry, and prospecting of any outcrop.
4. Ground geophysics. Magnetics and IP to trace structures and alteration under cover; see our magnetic survey guide.
5. Drill and report. Test the ranked targets and disclose results properly under NI 43-101.

Money follows the same pattern. NRCan’s exploration survey shows Ontario leading Canadian exploration spending in 2024, ahead of Quebec and British Columbia, with the three together accounting for almost two thirds of the national total, and Quebec expected to take the lead in 2025. For a junior with claims near known gold deposits in Ontario, that means competition for drill rigs, crews and assay capacity in a good year, and a reason to have targets ranked before the season opens.

Satellite data fit at the front of that list. Our satellite-based mineral detection analyses multispectral and hyperspectral imagery over a claim block to flag target zones, alteration halos, faults and fractures, so crews go first to the ground most likely to repay a till line or a drill hole. It shortens early exploration from months to days and lowers early-exploration cost by up to 80–85%, without ground disturbance. It does not replace till sampling or drilling. It tells you where to put them.

• Send: coordinates, KML/KMZ or a polygon of your Ontario claims, plus target mineral.
• Receive: high-potential zones, prospectivity heatmaps, estimated location and depth ranges and geological interpretation in PDF and GIS formats, in 5–20 business days.
• Premium+: TargetMax™ drilling-angle recommendations and interactive 3D models of vein structures.

We have scanned more than 100,000 hectares for 20+ mineral types in over 25 countries. Results are exploration targets, not resources. Draw your cells on mining.farmonaut.com (Map Your Mining Site), see a sample of satellite-driven 3D mineral prospectivity mapping, or ask for a quote through the mining query form. You can also write to us on the contact page.

Gold deposits in Ontario: frequently asked questions

Reviewed September 2026 against Natural Resources Canada’s gold facts and 2025 exploration survey, Ontario Mineral Inventory records for Kirkland Lake, Dome, Timmins, Detour Lake, Campbell and Williams, Ontario’s exploration plan and permit guide and MLAS page, O. Reg. 65/18, the Ontario heritage plaque for the Richardson mine, and the Alberta Geological Survey’s report on gold in Alberta rivers.

Production and reserve figures carry the year shown in the source record and are revised by the Ontario Geological Survey and the companies. Deposits and mines are named only as geological examples; Farmonaut did not discover them. The planner is a guide to timing and assessment work, not legal advice; confirm requirements with the Ministry. Nothing here is investment advice. Satellite targets are exploration targets, not mineral resources.