The wireless told me that steel made before the testing of nuclear weapons is much prised for making delicate things.
Not sure of the veracity of this so I’ve decide to throw the topic open and take questions and answers from the floor.

Yes the chap at the back, can we get a microphone to the chap with the pipe in the cardigan.

Peak Warming Man said:

The wireless told me that steel made before the testing of nuclear weapons is much prised for making delicate things.
Not sure of the veracity of this so I’ve decide to throw the topic open and take questions and answers from the floor.

Yes the chap at the back, can we get a microphone to the chap with the pipe in the cardigan.

correct.

I posted a thread a while back about salvaging WW2 stuff in the seas off Indonesia…

That story talked about this.

sarahs mum said:

I posted a thread a while back about salvaging WW2 stuff in the seas off Indonesia…

That story talked about this.

Yes that was the context in which I heard it last night, something about war grave ships disappearing.

https://www.straitstimes.com/asia/se-asia/malaysia-firms-plunder-sunken-wrecks-for-rare-steel-used-to-make-sensitive-medical

Can’t find my thread.

https://en.wikipedia.org/wiki/Low-background_steel

Peak Warming Man said:

The wireless told me that steel made before the testing of nuclear weapons is much prised for making delicate things.
Not sure of the veracity of this so I’ve decide to throw the topic open and take questions and answers from the floor.

Yes the chap at the back, can we get a microphone to the chap with the pipe in the cardigan.

sarahs mum said:

I posted a thread a while back about salvaging WW2 stuff in the seas off Indonesia…

That story talked about this.

Yes that was the context in which I heard it last night, something about war grave ships disappearing.

Oh, that is priceless.

I can immediately see one application of pre-nuclear-testing old iron. In neutrino detectors. These detectors are moved under a kilometer of rock, ice or water in order to remove all the stray radiation. Just a tiny grain of radioactive material in the metal of a neutrino detector can play havoc with the amount of radiation detected in the detection tank. It has happened.

Pre nuclear testing old iron is useful in medicine , low background steel is sought after for medical scanners.

Tau.Neutrino said:

Pre nuclear testing old iron is useful in medicine , low background steel is sought after for medical scanners.

Which makes me wonder. What else is in steel besides iron, carbon and alloying elements? I mean what other impurities from the ores and fluxes that have made their way down through the chain into the final product.

If they are digging the iron ore from the bottom of a deep hole how does that get contaminated?

mollwollfumble said:

Tau.Neutrino said:

Pre nuclear testing old iron is useful in medicine , low background steel is sought after for medical scanners.

Which makes me wonder. What else is in steel besides iron, carbon and alloying elements? I mean what other impurities from the ores and fluxes that have made their way down through the chain into the final product.

I’m sure that it is all documented.

AwesomeO said:

If they are digging the iron ore from the bottom of a deep hole how does that get contaminated?

It doesen’t That’s the point.
The problem comes abouit with processing it in the current atmosphere.

roughbarked said:

mollwollfumble said:

Tau.Neutrino said:

Pre nuclear testing old iron is useful in medicine , low background steel is sought after for medical scanners.

Which makes me wonder. What else is in steel besides iron, carbon and alloying elements? I mean what other impurities from the ores and fluxes that have made their way down through the chain into the final product.

I’m sure that it is all documented.

Yes. Somewhere in the bowels of the archives – the phrase “beware of the leopard” comes to mind.

Most iron ores are some type of iron oxide, usually hematite. I have some iron oxide nodules there that I found on the ground, southwest of Cloncurry. They assay 38% U3O8.

(I was using a portable scintillometer to pinpoint radiation that had been identified by airborne radiometer survey. I was searching for rare earth elements, which are often found with uranium.)

Michael V said:

Most iron ores are some type of iron oxide, usually hematite. I have some iron oxide nodules there that I found on the ground, southwest of Cloncurry. They assay 38% U3O8.

(I was using a portable scintillometer to pinpoint radiation that had been identified by airborne radiometer survey. I was searching for rare earth elements, which are often found with uranium.)

38% U3O8 is a huge percentage.

Follow on question for Michael V.

How does prospecting work now? eg. start by getting land-owner’s approval? or start using maps from somewhere?

I have images in my head of a lone prospector carrying a gold pan and geological hammer as he makes his way by horseback. Obviously that’s not how it’s done now.

mollwollfumble said:

Michael V said:

Most iron ores are some type of iron oxide, usually hematite. I have some iron oxide nodules there that I found on the ground, southwest of Cloncurry. They assay 38% U3O8.

(I was using a portable scintillometer to pinpoint radiation that had been identified by airborne radiometer survey. I was searching for rare earth elements, which are often found with uranium.)

38% U3O8 is a huge percentage.

Follow on question for Michael V.

How does prospecting work now? eg. start by getting land-owner’s approval? or start using maps from somewhere?

I have images in my head of a lone prospector carrying a gold pan and geological hammer as he makes his way by horseback. Obviously that’s not how it’s done now.

First, gather all information you can. Old company reports, government reports, geophysical data in the public domain, etc. Make a case to the CEO that there’s a possibility. A good enough story that he can raise money on. Then get the lease for exploration from the government. One will have to make promises about spending certain amounts of money each year (generally over five years). Then get landholders permission and traditional owners permission. Then go ahead. Map, sample interesting outcrops. If still interesting, soil sampling to home in. Then drill. Then explain why you didn’t find much.

For coal, generally, the mapping and surface sampling bits are omitted. (Coal very very rarely outcrops.)

Michael V said:

mollwollfumble said:

Michael V said:

Most iron ores are some type of iron oxide, usually hematite. I have some iron oxide nodules there that I found on the ground, southwest of Cloncurry. They assay 38% U3O8.

(I was using a portable scintillometer to pinpoint radiation that had been identified by airborne radiometer survey. I was searching for rare earth elements, which are often found with uranium.)

38% U3O8 is a huge percentage.

Follow on question for Michael V.

How does prospecting work now? eg. start by getting land-owner’s approval? or start using maps from somewhere?

I have images in my head of a lone prospector carrying a gold pan and geological hammer as he makes his way by horseback. Obviously that’s not how it’s done now.

First, gather all information you can. Old company reports, government reports, geophysical data in the public domain, etc. Make a case to the CEO that there’s a possibility. A good enough story that he can raise money on. Then get the lease for exploration from the government. One will have to make promises about spending certain amounts of money each year (generally over five years). Then get landholders permission and traditional owners permission. Then go ahead. Map, sample interesting outcrops. If still interesting, soil sampling to home in. Then drill. Then explain why you didn’t find much.

For coal, generally, the mapping and surface sampling bits are omitted. (Coal very very rarely outcrops.)

Isn’t the presence of coal able to be assessed from river water samples?

Peak Warming Man said:

Michael V said:

mollwollfumble said:

38% U3O8 is a huge percentage.

Follow on question for Michael V.

How does prospecting work now? eg. start by getting land-owner’s approval? or start using maps from somewhere?

I have images in my head of a lone prospector carrying a gold pan and geological hammer as he makes his way by horseback. Obviously that’s not how it’s done now.

First, gather all information you can. Old company reports, government reports, geophysical data in the public domain, etc. Make a case to the CEO that there’s a possibility. A good enough story that he can raise money on. Then get the lease for exploration from the government. One will have to make promises about spending certain amounts of money each year (generally over five years). Then get landholders permission and traditional owners permission. Then go ahead. Map, sample interesting outcrops. If still interesting, soil sampling to home in. Then drill. Then explain why you didn’t find much.

For coal, generally, the mapping and surface sampling bits are omitted. (Coal very very rarely outcrops.)

Isn’t the presence of coal able to be assessed from river water samples?

Not that I am aware of. I can’t even think how one might do that. Except maybe carbon and oxygen isotope work.

Michael V said:

mollwollfumble said:

Michael V said:

Most iron ores are some type of iron oxide, usually hematite. I have some iron oxide nodules there that I found on the ground, southwest of Cloncurry. They assay 38% U3O8.

(I was using a portable scintillometer to pinpoint radiation that had been identified by airborne radiometer survey. I was searching for rare earth elements, which are often found with uranium.)

38% U3O8 is a huge percentage.

Follow on question for Michael V.

How does prospecting work now? eg. start by getting land-owner’s approval? or start using maps from somewhere?

I have images in my head of a lone prospector carrying a gold pan and geological hammer as he makes his way by horseback. Obviously that’s not how it’s done now.

First, gather all information you can. Old company reports, government reports, geophysical data in the public domain, etc. Make a case to the CEO that there’s a possibility. A good enough story that he can raise money on. Then get the lease for exploration from the government. One will have to make promises about spending certain amounts of money each year (generally over five years). Then get landholders permission and traditional owners permission. Then go ahead. Map, sample interesting outcrops. If still interesting, soil sampling to home in. Then drill. Then explain why you didn’t find much.

For coal, generally, the mapping and surface sampling bits are omitted. (Coal very very rarely outcrops.)

That’s a great summary. Let’s see if I understand, at least partially.
So you start with whatever mineral you’re interested in, and whatever general location you’re interested in.
Track down whichever company has been mining it to start with and read the reports.
Government reports? What are those?
Geophysical data in the public domain would be from old mining journals, geoscience website, paper maps? Or more than that?
Case to the CEO – rather you than me.
Landholders permission and traditional owners permission. Is that easy?
Map.
Sample interesting outcrops. Pick and geological hammer?
Would you do field tests there, eg. flame tests, or simply by eye and experience? What would you send off for a full assay?
Is this the time you would overfly with magnetometer or geiger counter?
Would hyperspectral imaging or ground penetrating radar or seismic testing be any use?
“If still interesting”. By concentration of mineral and size of field, by distance to transport, by water and power availability or by all five?
Soil sampling to home in. Like gold panning, tracking down the source of heavy minerals by going up creeks, or like coring?
“Then drill” Essential.
Then explain why you didn’t find much. Oh dear.

I wonder if many minerals still exist that can be discovered by your lone prospector with a relatively low tech approach.
I imagine many fields were say gold is discovered would have been inspected numerous times and virtually nothing would be left on the surface or just below it.

Cymek said:

I wonder if many minerals still exist that can be discovered by your lone prospector with a relatively low tech approach.
I imagine many fields were say gold is discovered would have been inspected numerous times and virtually nothing would be left on the surface or just below it.

Wait till they figure out deep sea stuff, with three quarters of the planet gotta be some good stuff out there.

AwesomeO said:

Cymek said:

I wonder if many minerals still exist that can be discovered by your lone prospector with a relatively low tech approach.
I imagine many fields were say gold is discovered would have been inspected numerous times and virtually nothing would be left on the surface or just below it.

Wait till they figure out deep sea stuff, with three quarters of the planet gotta be some good stuff out there.

If they do that, and they want to throw away the manganese, I’ll take all the manganese I can get. I strongly suspect that manganese can be used as a 1:1 replacement for iron.

mollwollfumble said:

AwesomeO said:

Cymek said:

I wonder if many minerals still exist that can be discovered by your lone prospector with a relatively low tech approach.
I imagine many fields were say gold is discovered would have been inspected numerous times and virtually nothing would be left on the surface or just below it.

Wait till they figure out deep sea stuff, with three quarters of the planet gotta be some good stuff out there.

If they do that, and they want to throw away the manganese, I’ll take all the manganese I can get. I strongly suspect that manganese can be used as a 1:1 replacement for iron.

I doubt they actually throw it away when it’s worth more then $10/kg.

mollwollfumble said:

Michael V said:

mollwollfumble said:

38% U3O8 is a huge percentage.

Follow on question for Michael V.

How does prospecting work now? eg. start by getting land-owner’s approval? or start using maps from somewhere?

I have images in my head of a lone prospector carrying a gold pan and geological hammer as he makes his way by horseback. Obviously that’s not how it’s done now.

First, gather all information you can. Old company reports, government reports, geophysical data in the public domain, etc. Make a case to the CEO that there’s a possibility. A good enough story that he can raise money on. Then get the lease for exploration from the government. One will have to make promises about spending certain amounts of money each year (generally over five years). Then get landholders permission and traditional owners permission. Then go ahead. Map, sample interesting outcrops. If still interesting, soil sampling to home in. Then drill. Then explain why you didn’t find much.

For coal, generally, the mapping and surface sampling bits are omitted. (Coal very very rarely outcrops.)

That’s a great summary. Let’s see if I understand, at least partially.
So you start with whatever mineral you’re interested in, and whatever general location you’re interested in.
Track down whichever company has been mining it to start with and read the reports.
Government reports? What are those?
Geophysical data in the public domain would be from old mining journals, geoscience website, paper maps? Or more than that?
Case to the CEO – rather you than me.
Landholders permission and traditional owners permission. Is that easy?
Map.
Sample interesting outcrops. Pick and geological hammer?
Would you do field tests there, eg. flame tests, or simply by eye and experience? What would you send off for a full assay?
Is this the time you would overfly with magnetometer or geiger counter?
Would hyperspectral imaging or ground penetrating radar or seismic testing be any use?
“If still interesting”. By concentration of mineral and size of field, by distance to transport, by water and power availability or by all five?
Soil sampling to home in. Like gold panning, tracking down the source of heavy minerals by going up creeks, or like coring?
“Then drill” Essential.
Then explain why you didn’t find much. Oh dear.

>>>>>>>>>> Government reports? What are those?

States have Geological Survey Departments who undertake their own work. Often compilations and re-mapping, re-interpretation etc. Geoscience Australia also undertakes its own research, including geophysical stuff.

>>>>>>>>>> Geophysical data in the public domain would be from old mining journals, geoscience website, paper maps? Or more than that?

Nowadays, companies often run geophysical programs as part of their exploration. The data is handed to the government annually and at the exploration licence expiry that stuff becomes public.

>>>>>>>>>> Landholders permission and traditional owners permission. Is that easy?

Generally not. Requires patience, care, thoughtfulness, listening etc to negotiate an agreement. Often exploration is seen as “tomorrow they’ll be digging a big hole in the ground and polluting everything in sight”, which is a difficult mindset to overcome.

>>>>>>>>>> Would you do field tests there, eg. flame tests, or simply by eye and experience? What would you send off for a full assay?

No, no field tests at all. (Although I have panned soils and smashed rock occasionally.) Assays are the go, including the element one is targeting and often a suite of others that may be pathfinder elements or elements of secondary importance to the exploration. For instance, I wouldn’t analyse a rock for gold without arsenic and copper, and possibly tellurium and a suite of others depending on where I was. I wouldn’t analyse soils for gold without arsenic.

What would I send off? Interesting rocks. Gossanous rocks. Rocks with significant hydrothermal alteration. Rocks with sulphides. Rocks with unusual carbonates. Rocks with sericite. Rocks with visible mineralisation.

>>>>>>>>>> Is this the time you would overfly with magnetometer or geiger counter?

Yes, after mineralisation was established, to help pinpoint prospective areas that may not be obvious, or are completely hidden. For a radiometric survey, a multi-channel scintillometer is used (not a simple geiger counter). One can then look at the three important natural originating series: K, Th, U.

>>>>>>>>>> Would hyperspectral imaging or ground penetrating radar or seismic testing be any use?

Hyperspectral imaging has been used since the 1980s and significant resources have been spent developing that stuff. Both satellite and hand-held equipment are used. Ground Penetrating Radar is not used much. Seismic is used for sub-horizontal layered deposits eg coal, oil. Also, some companies use hand-held XRFs (X-Ray Flourescence Spectrometers), although getting licences for these instruments is difficult and time-consuming. I held a Radiation Safety Offers’s licence until this year to oversee the use, audit and training for portable XRFs.

>>>>>>>>>> “If still interesting”. By concentration of mineral and size of field, by distance to transport, by water and power availability or by all five? All those things are continually assessed. But yes. If it looks like there’s even a slight chance of discovering something economic, then proceed to drilling (which is often very expensive). To give you an idea, the least I have spent on a drilling program was around a quarter of a million dollars, and the most was 90 million dollars. Soil sampling to home in. Like gold panning, tracking down the source of heavy minerals by going up creeks, or like coring?

>>>>>>>>>> Soil sampling to home in. Like gold panning, tracking down the source of heavy minerals by going up creeks, or like coring? Sampling via hand auger, powered auger, or shovel and crow bar. Design of grid might be square (or rectangular if one has any notion about the geologic structure) on level ground, or ridge and spur on steep ground. A specific horizon (or horizons) in the soil or a specific depth would be targeted.

>>>>>>>>>> Then explain why you didn’t find much. Oh dear.

Yes. Mostly (>99%) one finds little, although “Technical Successes” (uneconomic discoveries) are relatively common. Most exposed mineral fields and mineral deposits have already been discovered.

mollwollfumble said:

AwesomeO said:

Cymek said:

I wonder if many minerals still exist that can be discovered by your lone prospector with a relatively low tech approach.
I imagine many fields were say gold is discovered would have been inspected numerous times and virtually nothing would be left on the surface or just below it.

Wait till they figure out deep sea stuff, with three quarters of the planet gotta be some good stuff out there.

If they do that, and they want to throw away the manganese, I’ll take all the manganese I can get. I strongly suspect that manganese can be used as a 1:1 replacement for iron.

Plenty of deep-sea stuff has been figured out (including the harvesting of manganese nodules). It’s off limits by international agreement.

I read a short story by B. L. Farjeon yesterday called In Australian Wilds. Farjeon was a gold miner during the Victorian Gold Rush, and the story is set in about 1851. It’s a first-person narrative in which he and two mates travel from Ballarat to Bendigo when gold is first discovered there. When they arrive they find that the primary gully is too crowded, so go to the next one, where they sink a shaft finding “at least twenty ounces of gold per bucket of [mullock].” From his description, finding large quantities at the time was so easy that anyone who tried came away rich (until they got to the grog shanty.)

btm said:

I read a short story by B. L. Farjeon yesterday called In Australian Wilds. Farjeon was a gold miner during the Victorian Gold Rush, and the story is set in about 1851. It’s a first-person narrative in which he and two mates travel from Ballarat to Bendigo when gold is first discovered there. When they arrive they find that the primary gully is too crowded, so go to the next one, where they sink a shaft finding “at least twenty ounces of gold per bucket of [mullock].” From his description, finding large quantities at the time was so easy that anyone who tried came away rich (until they got to the grog shanty.)

I have a piece of iron-oxide-cemented conglomerate from the bottom of a creek at Upper Tooloom where 20% of the gravelly clasts are gold nuggets. One field at upper Tooloom was actually called “The Cements”. The gravel was cemented with either calcium carbonate or iron oxide. Average depth to the gold was about 50 cm. The cemented gold-bearing horizon was up to 30 cm thick and in places ran >60% Au. A little two-man private alluvial mine downstream (and up a side valley) washed 10 – 30 ounces a day in the late 1990s, and they didn’t work too hard. The old-timers missed that bit.

Michael V said:

I have a piece of iron-oxide-cemented conglomerate from the bottom of a creek at Upper Tooloom where 20% of the gravelly clasts are gold nuggets. One field at upper Tooloom was actually called “The Cements”. The gravel was cemented with either calcium carbonate or iron oxide. Average depth to the gold was about 50 cm. The cemented gold-bearing horizon was up to 30 cm thick and in places ran >60% Au. A little two-man private alluvial mine downstream (and up a side valley) washed 10 – 30 ounces a day in the late 1990s, and they didn’t work too hard. The old-timers missed that bit.

False bottom?

Michael V said:

First, gather all information you can. Old company reports, government reports, geophysical data in the public domain, etc. Make a case to the CEO that there’s a possibility. A good enough story that he can raise money on. Then get the lease for exploration from the government. One will have to make promises about spending certain amounts of money each year (generally over five years). Then get landholders permission and traditional owners permission. Then go ahead. Map, sample interesting outcrops. If still interesting, soil sampling to home in. Then drill. Then explain why you didn’t find much.

For coal, generally, the mapping and surface sampling bits are omitted. (Coal very very rarely outcrops.)

>>>>>>>>>> Government reports? What are those?

States have Geological Survey Departments who undertake their own work. Often compilations and re-mapping, re-interpretation etc. Geoscience Australia also undertakes its own research, including geophysical stuff.

>>>>>>>>>> Geophysical data in the public domain would be from old mining journals, geoscience website, paper maps? Or more than that?

Nowadays, companies often run geophysical programs as part of their exploration. The data is handed to the government annually and at the exploration licence expiry that stuff becomes public.

>>>>>>>>>> Landholders permission and traditional owners permission. Is that easy?

Generally not. Requires patience, care, thoughtfulness, listening etc to negotiate an agreement. Often exploration is seen as “tomorrow they’ll be digging a big hole in the ground and polluting everything in sight”, which is a difficult mindset to overcome.

>>>>>>>>>> Would you do field tests there, eg. flame tests, or simply by eye and experience? What would you send off for a full assay?

No, no field tests at all. (Although I have panned soils and smashed rock occasionally.) Assays are the go, including the element one is targeting and often a suite of others that may be pathfinder elements or elements of secondary importance to the exploration. For instance, I wouldn’t analyse a rock for gold without arsenic and copper, and possibly tellurium and a suite of others depending on where I was. I wouldn’t analyse soils for gold without arsenic.

What would I send off? Interesting rocks. Gossanous rocks. Rocks with significant hydrothermal alteration. Rocks with sulphides. Rocks with unusual carbonates. Rocks with sericite. Rocks with visible mineralisation.

>>>>>>>>>> Is this the time you would overfly with magnetometer or geiger counter?

Yes, after mineralisation was established, to help pinpoint prospective areas that may not be obvious, or are completely hidden. For a radiometric survey, a multi-channel scintillometer is used (not a simple geiger counter). One can then look at the three important natural originating series: K, Th, U.

>>>>>>>>>> Would hyperspectral imaging or ground penetrating radar or seismic testing be any use?

Hyperspectral imaging has been used since the 1980s and significant resources have been spent developing that stuff. Both satellite and hand-held equipment are used. Ground Penetrating Radar is not used much. Seismic is used for sub-horizontal layered deposits eg coal, oil. Also, some companies use hand-held XRFs (X-Ray Flourescence Spectrometers), although getting licences for these instruments is difficult and time-consuming. I held a Radiation Safety Offers’s licence until this year to oversee the use, audit and training for portable XRFs.

>>>>>>>>>> “If still interesting”. By concentration of mineral and size of field, by distance to transport, by water and power availability or by all five? All those things are continually assessed. But yes. If it looks like there’s even a slight chance of discovering something economic, then proceed to drilling (which is often very expensive). To give you an idea, the least I have spent on a drilling program was around a quarter of a million dollars, and the most was 90 million dollars. Soil sampling to home in. Like gold panning, tracking down the source of heavy minerals by going up creeks, or like coring?

>>>>>>>>>> Soil sampling to home in. Like gold panning, tracking down the source of heavy minerals by going up creeks, or like coring? Sampling via hand auger, powered auger, or shovel and crow bar. Design of grid might be square (or rectangular if one has any notion about the geologic structure) on level ground, or ridge and spur on steep ground. A specific horizon (or horizons) in the soil or a specific depth would be targeted.

>>>>>>>>>> Then explain why you didn’t find much. Oh dear.

Yes. Mostly (>99%) one finds little, although “Technical Successes” (uneconomic discoveries) are relatively common. Most exposed mineral fields and mineral deposits have already been discovered.

> Nowadays, companies often run geophysical programs as part of their exploration. The data is handed to the government annually and at the exploration licence expiry that stuff becomes public.

Available where, how?

> Landholders permission and traditional owners permission. Is that easy? Generally not. Requires patience, care, thoughtfulness, listening etc to negotiate an agreement.

Well that rules me out. Diplomacy and tact are not parts of my resume. CSIRO was wise to keep me away from clients, I’ve lost more than one contract by lack of tact.

> What would I send off? Interesting rocks. Gossanous rocks. Rocks with significant hydrothermal alteration. Rocks with sulphides. Rocks with unusual carbonates. Rocks with sericite. Rocks with visible mineralisation.

Can you expand on that? I understand that metamorphic rocks with hydrothermal alteration can be very valuable. Sulphides can include lead etc. Unusual carbonates would be those other than limestone and gypsum. But what is “Gossanous” and “sericite”. “multi-channel scintillometer” is a new one to me as well.

> Hand-held hyperspectral imaging and XRF

I hadn’t realised that they made them so small.

> drilling program was around a quarter of a million dollars up to 90 million dollars

That’s a lot. Why so expensive? Because of cost per hole, depth or number of holes?

> “Technical Successes” (uneconomic discoveries) are relatively common

That’s what interests me most. Where, for example? Economics can change, as a result of other mines closing down, changes in power availability, transport or water availability, technological development, or value adding or new uses for materials. Is water supply a major problem these days? Can working mines be seasonal, eg. shut down during the dry season?

> Mostly (>99%) one finds little. Most exposed mineral fields and mineral deposits have already been discovered.

>99% failure rate is a heck of high percentage. Is there anything that can be done to improve the success rate in looking for mineral fields with no surface outcroppings?