Before anyone spends money on a licence, the best free research is already sitting in government archives: decades of company assessment reports, mineral occurrence databases and survey maps. This guide covers the agencies that hold them in British Columbia, the rest of Canada, Australia, the United States, South Africa, Saudi Arabia and Colombia, what each one offers, and how long company reports stay confidential before you can read them.
Agencies BCGS · GSC · MGS · GSWA · GSNSW · SGC · SGS
Data Reports · occurrences · maps
Markets Canada · Australia · South America
The BC Geological Survey is British Columbia’s provincial geoscience agency, and for anyone exploring in the province it is the first stop: it runs the ARIS archive of company assessment reports, the MINFILE mineral occurrence database and the MapPlace map viewer. Other provinces, states and countries have their own versions. Knowing which agency holds what, and how to search it, can save a licence holder months of repeated work.
Try it: When will that exploration report become public? →
The value is easy to underestimate. The BC Data Catalogue’s ARIS entry says the BC Geological Survey maintains more than 39,600 mineral assessment reports, filed since 1947 and describing exploration work that cost over 2.8 billion dollars. After a one-year confidentiality period, all of it is free to read. Much of that spending was on ground that is open again today. If gold is the target, our guide to government gold maps, Google Earth and old mine records shows how to layer this data.
“BC’s ARIS archive holds more than 39,600 reports describing exploration work that cost over 2.8 billion dollars.”
An assessment report shows what a previous holder sampled, drilled and concluded. Reading every report on and around a target is the cheapest due diligence there is, and it is often skipped.
The BC Geological Survey: ARIS, MINFILE and MapPlace
The British Columbia Geological Survey sits inside the provincial government and publishes most of what an explorer in the province needs. Three systems do most of the work.
ARIS: the assessment report archive
Companies holding mineral titles in BC file technical assessment reports to keep their claims in good standing under the Mineral Tenure Act Regulations. The BC Geological Survey reviews and indexes them in ARIS, the Assessment Report Indexing System. The reports cover geology, geophysics, geochemistry, drilling, prospecting and physical work. The catalogue entry notes that more than 620 reports also come with digital data as ZIP downloads, and that ARIS can be searched through its own web tool, through MapPlace web services, or downloaded as a database. The survey’s digital submission page confirms the data become available alongside the PDF once the one-year confidentiality period ends.
MINFILE: the mineral occurrence database
The MINFILE catalogue entry describes geological, location and economic information on more than 16,000 metallic, industrial mineral and coal occurrences in British Columbia, used by government, industry and academia. It downloads as CSV and spreadsheet files and as a KML loader for Google Earth, and it can be queried on MapPlace. For British Columbia geology at district scale, MINFILE and the survey’s geology layers together are the starting point.
MapPlace: everything on one map
MapPlace is the BC Geological Survey’s web map, where MINFILE occurrences, ARIS reports and other survey layers can be viewed and queried together. It is the quickest way to see which reports cover a block of ground before downloading them.
Claims change names and owners. Search ARIS by location first, then by any historical property names you find in MINFILE records, so reports filed under an older name are not missed.
If you are buying rather than staking, the same research applies. Our British Columbia claims buyer guide covers title checks and holding costs; the BC Geological Survey’s archive covers what work has already been done on the ground.
A BC desk study in five downloads
Suppose you are looking at a block of open ground in British Columbia. Before any fieldwork, five downloads from the BC Geological Survey and the BC Data Catalogue tell you most of what is publicly known about it.
- MINFILE as CSV or KML. Every recorded occurrence in and around the block, with commodity, deposit type and references.
- ARIS report footprints. The KML or web-map layer shows which assessment reports cover the ground; note each report number.
- The reports themselves. Download each PDF, plus the digital data ZIP where one exists.
- Survey geology. The BC Geological Survey’s digital geology for the area, to place occurrences and sample results in their host rocks.
- Current tenure. The provincial mineral titles map, to see which parts are open, held or recently forfeited.
A day spent with those five layers usually answers the questions a buyer or a new staker cares about: what the target is, who has tested it, how well, and what they left untested. It also shows whether recent work might still be confidential. Anything registered in the last year will not be on ARIS yet, and the calculator further down gives the routine release date.
The Geological Survey of Canada and the other provinces
Geological Survey of Canada
The federal agency is older than the country. Natural Resources Canada’s history page dates the founding of the Geological Survey of Canada to April 14, 1842, 25 years before Confederation. Today the GSC describes itself as the national organisation for geoscientific information and research, with programmes on minerals and critical minerals and on geoscience for the North. Its national geophysics, regional maps and publications complement the provincial data. Mineral titles, though, are provincial and territorial.
Ontario: bedrock geology, OMI and assessment files
The Ontario Geological Survey publishes bedrock geology of Ontario at provincial and regional scales, the Ontario Mineral Inventory of more than 19,000 occurrences, and assessment files. The Ontario Data Catalogue says the Assessment File Research Image database houses more than 85,000 assessment files, with airborne and ground geophysics, geology, geochemistry, drilling and trenching. The Ontario Assessment File Database description adds that files go back to the 1940s and can be viewed as KML in Google Earth through OGSEarth.
Manitoba Geological Survey
The Manitoba Geological Survey is the province’s research arm, and its public pages are a good primer on two commodities that attract searches: lithium and gold. The lithium in Manitoba page says granitic pegmatite contains the largest known lithium resources in the province, with the Winnipeg River–Cat Lake pegmatite field hosting the Tanco lithium-cesium-tantalum deposit in the Bird River greenstone belt. It also lists lithium pegmatites at Red Sucker Lake, Gods Lake, Cross Lake, Red Cross Lake, McLaughlin Lake and Wekusko Lake, and notes that Williston Basin brines have yet to be systematically evaluated. For gold in Manitoba, the survey’s Reports of Activities cover greenstone belts such as Rice Lake in the southeast. Our battery-metals exploration guide covers how pegmatite and other battery-metal targets are explored.
Manitoba’s assessment work page says reports become public three years after submission, or five years for airborne work, and that the open collection holds nearly 10,000 reports dating from the 1930s. Placer gold in Manitoba is a much smaller topic; the hard-rock greenstone belts are where the province’s gold work is concentrated.
Alberta Geological Survey maps
The Alberta Geological Survey says recent mineral exploration in the province has focused on lithium, uranium, base metals and industrial minerals. It publishes surficial and bedrock geology of Alberta, the Minerals of Alberta map (Map 655) and an interactive minerals map (AIMM), with GIS downloads. Its published products also include 3D models of geology and rock properties, a geological framework of the province and a GIS compilation of structural elements. For explorers looking at lithium in formation brines or at metallic targets on the Precambrian shield in the northeast, those layers are the starting point.
Australia: Geological Survey of Western Australia and Geological Survey of NSW
Geological Survey of Western Australia
The Geological Survey of Western Australia, part of the Department of Mines, Petroleum and Exploration, runs MINEDEX, GeoVIEW.WA and the WAMEX archive of company reports. The WAMEX page explains that explorers must report every year and that open-file reports can be searched and downloaded free, with harmonised drillhole and surface geochemistry extracted into a separate online database. Under the Sunset Clause in Regulation 96(4), reports held for five years may be released: each March the department publishes the list, current holders have two months to object in writing, and reports without objections are released from May. Objections are valid for no more than five years each. Tenure is covered in our WA mining tenements guide.
Geological Survey of NSW
The Geological Survey of NSW publishes MinView, the Seamless Geology dataset and DIGS, the archive of company exploration reports. Under the NSW annual report release policy, reports are released after a five-year confidentiality period, and annual reports from exploration licences and assessment leases for Group 1–6 and 10 minerals have been publicly released under the policy since 2022. NSW Resources is consulting on a revision that would add report types previously excluded.
Geological Survey of South Australia
The Geological Survey of South Australia delivers its data through SARIG, a free, no-login map portal covering geology, geophysics, regolith, paleodrainage and tenements, with 1:250,000 and 1:100,000 geology sheets available as PDFs or GIS layers.
When will that exploration report become public?
Assumptions: BC, one year from the work registration date (BCGS ARIS). Manitoba, three years after submission, five for airborne work (Manitoba Mines Branch). Western Australia, reports held five years may be released under Regulation 96(4); this tool assumes release in the May after the five-year mark, and a holder’s objection can delay it up to five more years (DMPE WAMEX page). NSW, five years after lodgement under the annual report release policy, or earlier if the title ends. Rules change and exceptions apply; confirm with the agency.
United States, Colombia, Saudi Arabia and South Africa
Idaho Geological Survey maps and other US state surveys
In the United States, each state has its own survey alongside the USGS. The Geologic Map of Idaho (M-9), for example, is a 1:750,000 statewide compilation with free PDF and GIS downloads and an interactive web version. State surveys also hold the larger-scale quadrangle maps that national compilations generalise away; our guide to 3D geologic maps and reading depth from dip shows how to use them. For federal land in the West, the claim record itself is held by the BLM rather than the survey.
Colombian Geological Survey (Servicio Geológico Colombiano)
The Colombian Geological Service, the Servicio Geológico Colombiano (SGC), publishes the Geological Map of Colombia 2023 at 1:1,500,000, along with earlier editions, the Geological Map of South America and a catalogue of radiometric dates viewable in Google Earth. The SGC open data portal lets users download data by topic or location.
Saudi Geological Survey
The Saudi Geological Survey’s National Geological Database brings geological and topographic maps, the Mineral Occurrences Documentation System (MODS), geochemistry, geophysics, borehole and surface-sample data into one portal, in Arabic and English. It also lists mineral potential assessment reports for metallic and industrial minerals.
South Africa’s Council for Geoscience
In South Africa the geological survey function sits with the Council for Geoscience, which offers free national geological, mineral and chronostratigraphic maps, with more detailed sheets on request. Prospecting and mining rights are handled by the Department of Mineral and Petroleum Resources, not the survey.
Agencies at a glance
The table below lines up the agencies in this guide by what an explorer usually needs from them: an occurrence database, a report archive and the rule for when company reports go public. Where a cell says “not covered here”, the agency may well have the data; this guide simply has not checked it.
| Agency | Occurrence database | Company report archive | When reports go public |
|---|---|---|---|
| BC Geological Survey | MINFILE (16,000+) | ARIS (39,600+ since 1947) | One year after work registration |
| Ontario Geological Survey | Ontario Mineral Inventory (19,000+) | Assessment files (85,000+) | After a confidentiality period (not covered here) |
| Manitoba Geological Survey / Mines Branch | Not covered here | Nearly 10,000 open reports from the 1930s | Three years; five for airborne work |
| Geological Survey of Western Australia | MINEDEX | WAMEX | Five years, each May, unless a valid objection |
| Geological Survey of NSW | Via MinView | DIGS | Five years, or earlier if the title ends |
| Saudi Geological Survey | MODS | Bibliographic database and open-file reports | Not covered here |
| Servicio Geológico Colombiano | Via the open data portal | Not covered here | Not covered here |
What is inside a typical assessment report
Assessment reports are written to prove that work was done, not to sell a project, which is exactly why they are useful. Most follow a standard shape: a title page and summary, a description of the claims, the work done, the results, the author’s qualifications and a statement of what the work cost. Manitoba’s assessment page lists those same parts as mandatory, down to the expenditure template.
The results sections are where the value sits. Look for sample location maps, assay certificates, drill logs with collar coordinates and hole directions, and the raw geophysical grids or profiles. A report that says a soil grid “returned no significant results” is still worth reading: the map shows exactly which ground was tested, at what spacing, and for which elements. Ground tested for copper at wide spacing may never have been tested for gold at all.
Three things to note for every report you read: the coordinate system used, the analytical method and detection limit for each element, and whether the samples were ever followed up. The first lets you plot the data correctly. The second tells you whether a “no gold” result would even have seen low-level gold. The third tells you whether the previous holder dropped the ground because it failed or because the money ran out.
Old geological survey maps
Old geological survey maps are a separate resource from the reports. Most agencies keep scanned copies of superseded map sheets, and they are worth checking for outcrop locations, old workings and field notes that later compilations smoothed over. In British Columbia, the BC Geological Survey’s older bulletins and maps sit alongside the modern digital geology; in Ontario, older OGS maps remain in the provincial archive. Use them for what the geologist saw, and use the newest map for what it means.
How to use survey data before you apply or buy
Survey maps and company reports are only useful if they are read in a set order. Whether the ground is in British Columbia or Western Australia, a practical desk routine for a new area looks like this:
- Map the occurrences. Pull MINFILE, OMI, MINEDEX, MODS or the local equivalent for the area and a buffer around it.
- List the reports. Use ARIS, AFRI, WAMEX or DIGS to find every open-file report whose footprint touches the ground.
- Read the geology. Put the survey’s largest-scale geology map under both layers.
- Extract the numbers. Record every drill hole, sample line and geophysical survey from the reports, with coordinates and dates.
- Check what is still confidential. Recent work on the ground may not be public yet; the calculator above gives the earliest routine release.
- Check tenure last. Confirm on the official cadastre which parts are open, held or for sale.
Reports from the 1960s to 1990s often use local grids or older datums such as NAD27 in North America or AGD66 in Australia. Convert every drill collar and sample before you plot it against a modern claim boundary.
For any BC property being sold or optioned, ask which ARIS reports cover it and read them yourself. Past spending, results and gaps are public after a year. General information, not investment advice.
Adding satellite screening to survey data
Survey archives show where people have worked. The gaps between their report footprints, and the ground under cover or forest that early mappers could not see, are where new targets often hide. Our satellite-based mineral detection analyses multispectral and hyperspectral data over your licence or area of interest to flag mineralised target zones, alteration halos, faults and fractures. Laid over MINFILE points, ARIS footprints and BC Geological Survey geology, the output helps rank which parts of a block deserve fieldwork first. Results are exploration targets to test, not resources.
- Input: coordinates, KML/KMZ or a polygon, plus country and target mineral.
- Output: high-potential zones, prospectivity heatmaps, estimated location and depth ranges, and geological interpretation, as PDF and georeferenced GIS files.
- Premium+: TargetMax™ drilling-angle recommendations and 3D subsurface models of vein structures.
- Timing and cost: 5–20 business days; early-exploration timelines cut from months to days, and costs lowered by up to 80–85%.
We have scanned 100,000+ hectares for 20+ mineral types in 25+ countries. Draw your area on mining.farmonaut.com (Map Your Mining Site), ask for a price via the mining query form, or see a sample of satellite-driven 3D mineral prospectivity mapping.
Every soil line and drill hole in an old report is ground that does not need to be disturbed again. Reading the archive first, and screening from satellite, cuts the fieldwork needed to reach the same answer.
Find the gaps between the old report footprints
Send us your licence or area of interest. We return ranked target zones and GIS files to overlay on survey geology, occurrence points and assessment report footprints.
Frequently asked questions
What does the BC Geological Survey provide?
The BC Geological Survey runs ARIS, with more than 39,600 assessment reports filed since 1947; MINFILE, with more than 16,000 mineral occurrences; and MapPlace, the web map where they can be viewed and queried. It also publishes geological maps and geochemistry for the province.
How long are British Columbia assessment reports confidential?
One year from the work registration date. After that, the British Columbia Geological Survey publishes the report as a PDF on ARIS, with any digital data as a ZIP download.
What is the difference between the Geological Survey of Canada and provincial surveys?
The Geological Survey of Canada, founded in 1842, is the federal geoscience agency with national geophysics, maps and research. Provincial surveys such as the BC Geological Survey or the Manitoba Geological Survey hold provincial maps, occurrence databases and the assessment reports tied to provincially issued mineral titles.
Where can I get data from the Geological Survey of Western Australia?
Through MINEDEX for deposits, GeoVIEW.WA for maps and WAMEX for open-file company reports, all free. Reports held for five years may be released each May under the Sunset Clause unless the holder lodges a valid objection.
Where is lithium found in Manitoba?
The Manitoba Geological Survey says granitic pegmatite holds the province’s largest known lithium resources, especially the Winnipeg River–Cat Lake field with the Tanco deposit, plus pegmatites at Red Sucker Lake, Gods Lake, Cross Lake, Red Cross Lake, McLaughlin Lake and Wekusko Lake.
Does the Colombian Geological Survey offer free maps?
Yes. The Servicio Geológico Colombiano publishes the Geological Map of Colombia 2023 at 1:1,500,000 and an open data portal with downloadable datasets by topic or location.
What is a mineral assessment report?
It is the technical report a claim holder files to show that required exploration work was done, so the title stays in good standing. It usually includes maps, sample and assay results, drill logs and a statement of costs. In British Columbia, Manitoba, Ontario, Western Australia and NSW, these reports become public after a confidentiality period, which makes them one of the best free sources of exploration data.
Reviewed September 2026 against the BC Data Catalogue entries for ARIS and MINFILE, the BC Geological Survey’s digital submission page, Natural Resources Canada’s history and GSC pages, the Ontario Data Catalogue and Ontario Assessment File Database description, the Manitoba Geological Survey lithium page and Mines Branch assessment work page, the Alberta Geological Survey mineral exploration page, the WA Government’s WAMEX page, NSW Resources’ annual report release policy page, the Idaho Geological Survey, the Servicio Geológico Colombiano and the Saudi Geological Survey’s National Geological Database.
Database counts, confidentiality rules and agency names change; check each agency before relying on a date or number. The calculator gives routine release dates only and ignores exceptions. Nothing here is investment advice. Satellite targets are exploration targets, not mineral resources, and need sampling and drilling to confirm.
Berks Gold Limited
Mwerezi Minerals Company Limited
Congo Mining Solutions
Mining SARL
SenGold Invest SAS
Sania Corporation
Sean Mining Limited
NTS Group (Pty) Ltd
Mine4Africa
Lithspo Minerals Limited
Tintina Mining Group
Dalgety Minerals Pty Ltd
Vortex Minerals Pty Ltd
Faith At Work (Pty) Ltd
Geotech Mining Solutions plc
Vulcan International Limited
Kidepo Associates
GKY Mining
Alkimy SARL
Double A Trading
GemSprout Metals Limited
Qader Group
Ileys General Trading
SG Gold Mining LLC
VRV Global Pte Ltd
Omsri International FZE
G.I.T.T.
Jaunita Erss Ltd
