Hard rock gold prospecting

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Thanks Macca and Jethro for your vote of confidence.
A bit of alluvial gold was not what I was looking for. I wanted to find enough to justify a mine. A bit ambitious you think? My Dad used you to say, "If you aim at nothing you'll always hit it."
Some years ago I was invited to speak to a group of gold prospectors in LA. I was used to speaking to groups in California on Opals but never gold so this was something new. I turned up at what seemed to be a church hall expecting about 10 - 20 people max. The place was packed - standing room only! What to do? Instead of a lecture I tore into it like a wild dog!
My opening sentence: " I saw on your notice board as I walked in that there's a trip planned for next weekend. You are warned not to forget your small glass phials to keep all that gold in you're going to find. Ha! Ha!" In Australia you are warned to go in a car or ute with decent springs. We often find big ones. "Aussie bullshit".This from a huge bloke sitting in the front row. Long hair, tattoos , a nose ring and I reckon, hairs on his teeth.. In the deadly silence that followed , I ignored him, turned and put in my first slide. Behind me there was a growing mutter. The first slide hit the screen and there was an audible gasp. They were staring gobsmacked at a couple standing in the backyard of a house. The husband was holding an enormous lump of gold : the Hand of Faith. I rubbed it in. Young blokes, old blokes, kids all staggering under the weight of fair dinkum Aussie nuggets. The Welcome Stranger, the Holtermann Nugget taller than the chap steadying it.
I switched off and turned. It started slowly at first then built up until the entire hall has on its feet clapping and cheering!
I told them about the WA goldfields, about the miners at Hill End smashing huge lumps from a collapsed wall because they were too heavy to get to the surface.
Those blokes had gold fever. I've gold fever and I'll bet you do too.
I decided to get some science. A mate suggested Radiometric data. I looked it up. Data collected by planes with high tech gear measuring the natural variations if the gamma rays which result from the natural radioactive decay of potassium uranium and thorium. I was about to give up. But I remembered my Dad and decided to keep going.
I'm glad I did.
 
The Geophysics department in each state can help track down the data for the area you're interested in. The NSW department was both helpful and friendly. I found the pages I was looking for but they were filled with squiggly lines and they meant nothing. But at the end was a summary of the data: Quaternary Alluvium Deposit. This applied to my area and not to areas 20 kms on either side.Here's a summary.
1. The area is likely to contain gold, platinum and precious stones. The result of Hydro Thermal Activity. In other words, Hot Water.
2. If a stream of hot water smashed into sandstone it would slow down and drop gold into the cracks and fissures, sandstone being Porous. This changes the nature of the sandstone and it becomes Quartzite.
3. The soil colour of the area is a light brown and not the red/orange colour of the soil on either side.
4. Deposits are usually shallow. Often likened to the soil or overburden covering an ore body like a blanket. Placer Deposits means metal detecting.
I read somewhere that over 50% of all gold recovered is from quartzite.
Next Step: seek permission from the landowner to prospect. If you're up front, honest and transparent you'll get friendly co-operation. A lot of landowners have had negative experiences from mining companies so they will be wary. The first thing to get clear is that all minerals found under their land belongs, not to them, but to the Crown. This usually upsets them as it seems so unfair. I point out that I have to gain Government permission to prospect which is costly and the Exploration Licence includes a refundable Bond of $10,000 should I damage and road , fence etc. I have printed a Permission to Enter form which lists the things I won't do e.g. bring a dog, or a firearm. I will respect all roads and leave all gates as I find them etc. Drill holes will be filled or capped. I will seek their permission to light a fire. I will notify them of my comings and goings. The Exploration Licence gives me total rights to a designated area (mine was 27 sq. kms) and can be for up to to 6 years. Mine is for 2 years but I have the right to extend that and also to change the designated area. If I find anything, I'll sit down with him and negotiate an agreement.
My first landowner recounted family stories from the Depression era of a lone cyclist prospecting on numerous occasions. They never saw him but saw the tyre tracks and signs of digging.
Everything was falling into place.
 
And finally. Never mention the word "gold" in the local pub or anywhere else. The locals know or suspect you're prospectors so don't make things harder for yourself. Have an answer ready: gypsum, magnesium, arsenic ( a good indicator of gold but they're not to know that), or simply," we're just sniffing around to see what might be a possibility."
Never take for granted that the prospect you've worked so hard for is secret. A magnetic tracker takes only seconds to attach to a vehicle.
Check out the NSW Dept. of Planning and Environment for costs associated with an Exploration Licence. If you're nervous about applying for a Licence you can always use a Mining Agent. But be careful. Get a quote and make sure they stick to it. I used an Agent because I wasn't confident to work through Native Title regulations. They sorted it out quickly. But really, if you take your time and are not too proud to ask for help you'll get there. No sweat. -
Here are some well known mines that manage to make money on low ore grades: Cadia Valley(Newcrest Mining) - 1.22G/T, Ravenswood
(Resolute Mining) - 2.09 g/t, Kalgoolie (Newmont/Barric) - 2.13 g/t, Super Pit (Newmont /Barrick) - 1.56 g/t, St Ives (Goldfields) 1.8/gt

Mineral Exploration is a crazy business. All you do is spend and work in freezing cold or hot dusty conditions putting up with snakes, flies and dust. You might find gold but that's not the point. You have to find enough gold bearing ore to justify a mine. You might work for 3 or 4 years at the same prospect and still not succeed. But if you do - then the reward is in millions when you sell your licence to a big miner.
But don't be deceived. It's the biggest gamble you'll ever face.
But it's a lot of fun.
 
Hey guys I have the correct answer for your diamond core drill problems , I have worked with industrial diamonds for donkeys years.

Quartz is not just hard but its also very abrasive , it requires soft diamond segment bonds and different diamond concentration (harder segments are used in softer rock like sandstone.)

You need diamonds correctly matched to the quartzite , contact Asahi Industrial Diamonds in Sydney and they will advise you options that will give you the fastest cutting rates and good diamond life .

Just tell them the rock type and they will tell you precisely what you need.

As an example for you , we had diamond segments on saw blades from another supplier that lasted only 100 - 280 lineal metres in black quartzite , Asahi supplied segments that lasted over 2000 metres of life and gave fast cutting speeds. Happy as !
 
Hi Crevicesucker I have been cutting a lot sandstone for the garden beds,and have felt that 14 inch blade that come with the saw does not cut 100%.
So I will into that a bit more. :Y:
 
grubstake said:
Harlequin said:
The drill is a Shaw Backpack diamond core drill - petrol powered. I know that quartzite is extremely hard but I expected it to handle the quartzite easily but that was not the case.

Looks like you've got a nice piece of gear there: http://www.backpackdrill.com/

Shaw's Field Experiences page shows their drill even being used successfully in jade boulders, which I thought were hard as the hobs of hell, so your difficulties with quartzite are surprising. What sort of penetration rate are you achieving?

Shaws should give the option of different diamond bonds for different materials but I see no mention of it on their website.

If Shaws wont supply it you will find other suppliers in Oz will retip your worn bits .

tell them what RPM the drill runs at as speed is critical , too slow and the diamonds will fracture or will cut like shettt. Ideal surface speed is 24 - 36 metres per second for diamond blades . Not sure what a 41 mm core drill should be , ask Asahi
 
thedigger said:
Hi Crevicesucker I have been cutting a lot sandstone for the garden beds,and have felt that 14 inch blade that come with the saw does not cut 100%.
So I will into that a bit more. :Y:

14 inch blades should be dime a dozen , there are some crap ones but also many good diamond products that come out of China because they have been using industrial diamonds for cutting and polishing stone for thousands of years.

Just try spending a little bit more money when you buy one and give them plenty of water . Wet cutting makes the diamonds cut faster , last longer and stops you getting silicosis
 
Thanks for the well informed info re diamond cutting.Sorry I haven't replied sooner as I have only just read your post as I have been in the midst of moving house. I will certainly follow your advice.
 
How is quarts abrasive ? Ive had 9com Longyear bits down the hole polished to hell , 10 mins to strip it with 9kn on it plus 1000mtrs of rods, once ur bit is sharp you can drill quarts and easy get 6-800 off a bit
 
I have written permission to prospect for gold over approx 180,000 acres. We are working on one particular property of approx 450,000 acres with a government licence (Exploration Licence) over 27 square kilometres. I woke this morning to discover that a Chinese gold mining company has applied for an Exploration Licence covering almost the entire property plus an enormous area south of us over which we have owner permission. They have not sought permission to enter. The northern boundary of their application comes right up to our EL boundary. Apparently they can do this but if their application is successful they still must get landowner permission to enter (?!)
How did they know about us? They lodged 10 applications in nearby areas on the same day!
Questions, questions.
Harlequin
 
Harlequin said:
I have written permission to prospect for gold over approx 180,000 acres. We are working on one particular property of approx 450,000 acres with a government licence (Exploration Licence) over 27 square kilometres. I woke this morning to discover that a Chinese gold mining company has applied for an Exploration Licence covering almost the entire property plus an enormous area south of us over which we have owner permission. They have not sought permission to enter. The northern boundary of their application comes right up to our EL boundary. Apparently they can do this but if their application is successful they still must get landowner permission to enter (?!)
How did they know about us? They lodged 10 applications in nearby areas on the same day!
Questions, questions.
Harlequin

Did you lodge your EL online ?

How many online departments or processes were there that could have been hacked or where they could read any notification published online ?

:8
 
Digga said:
How is quarts abrasive ? Ive had 9com Longyear bits down the hole polished to hell , 10 mins to strip it with 9kn on it plus 1000mtrs of rods, once ur bit is sharp you can drill quarts and easy get 6-800 off a bit

Are you saying your diamond matrix was glazed or polished ?

can you post a photo ?

Look up the Cerchar abrasive index numbers for the quartz you are drilling.

There is data available online for most areas if you look.

Its not just hardness thats a problem for cutting tools , as mentioned above , the abrasiveness is a big factor and it varies massively and the diamond bond should be designed to suit that rock , if you have enough water then i would expect the bond is too hard.

An example for you is a rock saw i designed was getting around 5 years life from wear pads in Sydney sandstone , when it was put onto a job cutting pure quartz reef 600 - 1000 mm thick , the wear plates were smashed within 3 months.

5 years versus 3 months is a service life wear factor of 20 times difference.
 
Not much to report Sprint32.
There is nothing I can do except wonder where they got my research material from. Well, that's not quite true as they could only have got it from two sources and I'm not prepared to take either of them on.
And to make matters worse, Covid wiped us out as we were unable to work for over a year.
However, I have the satisfaction of knowing that we found gold. In fact we found gold on our first day of exploration! 2.32 grams per ton doesn't sound much but it placed us half way up the ladder between the top mines and the lowest. A "thumbs up" to spending time doing research!
I can still remember that first day looking for a base camp site. A huge outcrop of white quartzite got top billing - especially when I noticed the stunted trees stretching away to the north. They were dry and seemed close to death but I knew that was for appearances only. They had a desperate look about them - hoping for a passing dog to notice them! But to a prospector they had a message: most trees have deep roots that seek water- the roots of gum trees can be nearly a hundred feet in length. These had roots but were mostly horizontal vegetation . In other words their roots could not go any deeper because something was stopping them - an ore body perhaps?! A "thumbs up" to paying attention to vegetation as well as the ground! And by the way, a high proportion of gold bearing ore bodies travel in a north south direction so you can see why we set up camp near those trees.
Not sure what I'll do next.
Regards,
Harlequin
 

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