How to Read an Old Mine Shaft (and Find the Gold Everyone Walks Past)

Here's something that took me years to properly understand. On nearly every old mine you'll ever walk up to, the easiest gold isn't down the shaft. It's sitting on the slope below it. It's been breaking off the reef and rolling downhill for thousands and thousands of years, long before anyone turned up with a detector. And almost every modern day prospector has walked straight past it, because they're all crowded around the hole.

In this article, I'm going to show you exactly how to find that downhill gold. But first we need to read the shaft itself, because the hole tells you where the slope is.

Reading the old workings

If you've done any detecting around the goldfields out here, you'll have come across old workings. Might be a proper timbered shaft, might be a caved-in hole with a mullock heap beside it, might just be some old scratchings and a costean (that's an old exploration trench the miners dug to chase a reef along the surface). The natural thing to do is have a detect right around the collar and move on.

But somebody sank that shaft for a reason. They found high-grade gold right there, and they followed it down. Which means that hole, and the walls of that hole, are absolutely packed with information, if you know what you're looking at.

Grab a cuppa, because this is a longer one. We're going to properly pull an old shaft apart and turn it into a search plan.

Three parts: reading the hole, chasing the reef along the ground, and then the big one, the slope below the shaft.

At the end I'll walk you through a whole imaginary site so you can see it all come together.

▎ Getting started? Check out what to look for when you first step out of the car at a new location. It covers the foundational skill of reading ground before you even switch the detector on.

The one idea it all hangs on

The old-timers did not empty these workings of gold. They couldn't. They dug thee asiest ore they could reach, using only a pick and a candle, and they left the rest, because they were working blind. When the ore reached the surface, they sorted by eye.

You've got a modern metal detector that sees through the dirt. So an old shaft isn't the end of the gold. It's a sign post pointing at where the gold still is. Everything in this article comes back to that.

This is why these overlooked gold zones at historic workings are so valuable, the zones the old timers missed or bypassed are often sitting right there, waiting.

Now, how to read a shaft.

Part one: reading the hole

You walk up to an old shaft, and before you switch that detector on, I want you to just stop and look down into it.

Now, safety first, and I mean this! Do not lean over the edge. Do not climb on the lip of an old shaft. Those old timbers are rotten, the ground around the collar can give way under you, and old workings can hold bad air that'll drop you before you even know something's wrong. There can also be a winze, a hidden second drop inside the shaft, that you'll never see from up top. You start to read a shaft from a safe distance, feet safely on the ground, and if you're not sure the ground is solid, you don't go near it. OK?

Lecture over, but I mean every word of it.

What you're looking for in the wall of that shaft is the thing they were chasing. Usually it's a vein or a reef of quartz (that white or greyish rock), and very often it's stained, all rusty and orange with iron. We call that ironstone staining, or a gossan.This can be highly oxidised cap sitting over a mineralised structure. In plain English, it's the rusty scar the gold-bearing rock leaves behind as it breaks down.

That vein in the wall is the ore body. It's the actual thing they dug the shaft to follow, frozen there in the rock for you to read.
Think of it like this. Imagine someone dug a fence-post hole and left the post sitting half in the ground, leaning off to one side. You can see straight away what they were doing, and which way it leans. That's your shaft wall: the reef, and the Two things I want you reading off that wall. First, which way the vein runs, its direction across the countryside; and secondly, how steeply it leans into the earth.

Two different things, each with a name, and we'll get to both. For now, just note them.

Quick question while we're here. How many old shafts have you detected around without ever really looking into them? I did it for years myself before the penny dropped, so no judgement here.

Part two: chasing the strike

So we've read the shaft. We've found the reef in the wall, and we've seen how it leans and which walls of the shafts you can see it in.

Now, lets turn that into actual ground to cover, because that direction you just read tells you where to walk for hundreds of metres out from the hole, in two directions, most of it ground that's barely been touched.

The direction the reef runs is what geologists call the strike. It's one of those geology words that sounds fancy but means something dead simple. The strike is just the compass direction the ore body runs along the ground. If you could follow that reef as line on the dirt, that line is the strike. That's it!

So sight along that vein in the shaft wall. See which way it's heading, north-south, north-west, east-west, whatever it is. Now extend that line out across the ground, in both directions.

Then, and this is the good part, look for the ground to confirm it available and not locked up in someone elses tenement. Looking along that line, you'll often find other clues sitting right on the same line. Ar ow of costeans. A line of other shafts or little scratchings. A trail of white quartz rubble on the surface. Sometimes even a change in the soil colour or the scrub, following the same bearing. When you see three or four old workings lined up like bead. That string is the strike, and the old-timers surveyed it in for you ah undred years ago without even knowing they were doing you a favour.

Now, remember I said to note two things off the shaft wall? The direction is the strike, done. The other one, how steeply the reef leans into the ground, is called the dip. Strike is the direction it runs; dip is how steeply it tilts down.

And the mistake to avoid here, a lot of beginner prospectors assume that the gold stopped where the shafts stops. It did't! The old-timers cherry-picked the fat, rich, easy bits. They didn't work the reef out to nothing. That structure keeps running well past the last hole they sank.

Working the corridor

So instead of gridding a tidy circle round the collar, detect a corridor. A strip that follows the strike line, maybe a sweep-width or two either side of it. Work out from the shaft in one direction for a good while, then head back and work the other direction. You're following the strike — not searching the whole paddock at random, and not just hammering the aread just around the collar.

Pay real attention to where the old workings thin out and stop. The ends of a worked line are often where the old-timers ran out of easy gold, or the lode ran out under a bit of soil cover where they simply could see through.

The gold didn't stop. Their eyesight did. They were working by what they could see on the surface, and the moment the reef ducked under a bit of dirt, they lost the line. You've got a detector that sees straight through that cover.

And here's a beauty. If you've got two shafts sitting on the same strike line, the untouched ground in the gap between them is worth a slow, careful grid. They sank a shaft at one spot, and another one over there, on the same reef. What's in the middle? The same material goes between the two shafts, and is often barely touched, because the richest, most obviousb its were at the two ends where they chose to dig. That gap is some of the most under-detected ground on the whole field.

A practical way to cover it, because "detect a corridor" is easy to say: treat the strike line like a road, and grid across it in lanes. Walk back and forth across the line, moving steadily along it, so your coil is always crossing where that reef. Remember the load will wanders a bit (and they do wander, they're not drawn with a ruler),you're still cutting across it every pass.

The big mistake, and I've made it plenty myself, is grinding away for hours right on the collar, on the mullock heap. That heap is the most flogged patch of ground on the field.

Every man and his dog has swung a coil over it since the seventies. Give it pass, sure the odd bit has been thrown up in the past , But don't build your day around it. The value's out along the line, in the gaps, and past the last of the workings.

But there's a whole second dimension to this that has nothing to do with strike. It's not about where the reef runs. It's about which way the gold's been falling.

Part three: the downhill gold

Right at the start, I told you the easiest gold on the whole site is usually not at the shaft, not down the hole. This is where I make good on that.

That shaft is very often sitting on, or right near, a high point in landscape, a bit of high ground. And there's a proper reason for that. Quartz is hard rock. It's tough, it resists weathering. So when everything around it is slowly wears down over millions of years, that hard quartz reef stands up a bit proud of the land. It harder to erodes. Gold reefs very, very often form these low ridges and rises, and the old-timers, chasing that quartz, sank their shaft up on the high bit. That's why so many old workings are up on a rise.

Now think about the timescale. Not a hundred years since the gold rush. Think in terms of thousands of years. Tens of thousands. Hundreds of thousands, even. Long before anyone turned up with a pick and a shivel, that gold has been physically breaking out of the top of that quartz reef. Heat and water and time all work away at it, and the gold that as locked in there gets freed.

Once it's free, gravity's got hold of it. Rain moves it. The slope moves it. And bit by bit, grain by grain, that gold creeps downhill, away from the source.

Picture a guy walking down a hill with a leaky bucket of paint. Although still full of of paint when he gets to the bottom, but he has left a the trail of paint down the slope behind him. Your gold does exactly the same thing off that reef. The reef's the leaky bucket. The slope below is the trail.

There's a couple of proper words for this, and I'll give them to you because you'll hear them thrown around: eluvial gold and alluvial gold. Sounds technical.

Elluvial gold means is gold that's broken away from its source and moved a short way down the slope, where as Alluvial gold is gold that has made it all the way down into a proper creek or river yet.

Elluvial gold hasn't been bashed around in a river for miles, it's often coarser, chunkier, more nuggety than the worn-down stuff in the creeks. And it's frequently sitting nice and shallow, because it hasn't had time to work down from the surface. It reaches a 30-50 centimetres down, not a hundred metres.

Shallow,coarse gold on a slope isn't the consolation prize. It's the exact target your machine is built for, and it's the stuff the old-timers couldn't be bothered with.

Working the fan

So, what you actually do. From the shaft, work out which way the ground falls away, the downhill slope. Don't guess it, have a proper look, because sometimes it's subtle. Then detect a fan-shaped zone spreading out downslope from the reef. Narrow up near the reef, and widening out as you go down the hill, because the further the gold travels, the more it spreads sideways.

Within that fan, watch for the little traps where gold likes to hang up and concentrate:

A slight bench or flat spot partway down the slope. Gold rolling down hits that flat and stops.
The base of the slope, where it flattens off into the valley. That's an important zone.
A shallow little drainage line running down the slope. Gold funnels into it.
Behind a bar of harder rock crossing the slope. It acts like a natural rifing the gold coming down.

Anywhere the gold's downhill run gets slowed or stopped, it can pile up.

Now, remember dip, the one I told you to keep in your back pocket? ere's where it earns its keep. Dip is how steeply the reef leans into the ground. If that reef leans over at an angle, say it leans toward the north, then underground the ore body is offset that way as it goes down, and the gold shedding off it favours the northern, downhill side. When the dip direction and the downhill slope line up the same way, that downslope facing. That's the sweet spot.

And this is the mistake that costs people gold every weekend they're out. They detect uphill of the shaft. They detect along the reef. And they treat the slope below the shaft as waste ground and never swing a coil over it. That is backwards. That whole slope is the reason the shaft exists. Someone found gold on the surface first: gold that had already shed off the reef and worked its way downhill to where they could spot it.

The downhill scatter came before the shaft, by thousands of years. Skip that slope and you'll be skipping the very gold that started the whole thing.

Putting it all together: walking an imaginary site

The best way to tie this all toegther, is to pretend to visit an imagery gold spot. This is a made-up spot — I'm not sending you anywhere real, I'm building one so you can see the thinking. You'll swap in your own numbers when you're standing on the real thing.

You're walking through the scrub and you come across an old shaft. Timbered collar, mullock heap beside it, the whole bit.

First — you stop. Keepping your feet on solid ground, and read it. You look at the wall of the shaft and see a quartz vein, rusty-stained, running through the rock. You sight along it. Let's say it runs roughly north-west to south-east. That's your strike. It's leaning over a bit as it goes down — toward the south-west. That's your dip.

Second — you stand back and look for confirmation along stroke. Sure enough, off to the south-east, maybe eighty metres away, there's another old caved-in working, sitting right on that same north-west to south-east line. Great!

Two beads on the string. Your strike is confirmed, and you didn't even need a compass — the old-timers drew the line for you.

Third — you plan your detecting corridors. You're going to work the strike line both ways. North-west out from the shaft into fresh ground past the collar, gridding across the line in lanes. And south-east — here's the good bit — that eighty-metre gap between your shaft and the second working, has the same reef running right through it, probably barely touched. That gap goes straight to the top of your list!

Fourth — and this is the one you don't skip — you read the slope. The ground falls away to the south-west. Now hang on, which way did the reef dip? South-west. The dip and the downhill slope line up. That's your sweet spot. So you work a fan spreading downslope to the south-west, narrow near the reef and widening as it goes down, and you slow right down at that flat bench halfway down and at the base of the slope where it levels out.

Look what's happened. One shaft. And you've now got the north-west extension, the south-east gap, and the south-west downhill fan with two natural traps inside it. That's not one roll of the dice — that's four or five good rolls, all read off one hole in the ground in about ten minutes of standing there and thinking.

Before you go swinging a coil

Next time you find an old shaft, you won't just see a hole in the ground. You'll see a direction, and you'll see a slope. Read the reef, chase the strike both ways, and work the ground downhill where the gold's been shedding away..

The critical last step: legal access

The tricky part is finding these old workings in the first place , now you got to make sure you've got the legal right to be there before you even get out the car. Old workings very often sit inside somebody's live tenement, not on open ground, so you always check first. Every time!

For a clear breakdown of what you need to know before you go, read where you can go in Western Australia It covers miner's rights, tenements, and exactly how to check.

That's a big part of why I built GoldProspectingWA.com. You can see the old workings and historical shafts, check which tenements are open ground, and dig into the geology to work out which reefs are worth chasing. Have a look around before your next trip.