Gold & Its Association With Ironstone

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malri_au said:
some of what i teach relates to iron/gold and it's association.

keyword from above that Goldierocks mentions above is 'precipitate'.

how? gold compounds. elements that it can bind with at different conditions.under the right conditions,iron precipitates gold.

how many gold compounds do you know?
There are a number - at high temperature under reducing conditions it bonds with hydrogen sulphide to form gold bisulphide ions in solution. At low temperature, salty and oxidising conditions (and sometimes at higher temperature) it bonds with the chlorine in the sodium chloride to form gold chloride ions. Lesss common are bonding with natural cyanide in soils, with thiosulphate ion in oxidising sulphide orebodies. It even occurs in a water-soluble form in calcrete (calcium carbonate) soils.
 
goldierocks said:
Deepseeker said:
goldierocks said:
We even find gold precipitating as platings on tree roots (I assume because of the carbon), and in the veinlets within leaves. It moves around.

Yes, I have read a number of times now online where people have mentioned tree roots being found encased in gold, a bullet shell found in a creek in Tasmania that has become gold-plated, and even a coin found in a stream in Alaska that has become plated with gold as well. As yet though, no matter how hard I have searched I haven't found a single photo or paper in relation to such phenomenon. Surely, without any scientific evidence of such claims they simply remain mythical, B.S or "anecdotal"?

I have read of research regarding gold found in leaves of trees, and that does make sense if it is being pumped up from the ground by the tree. Although surely that is a completely different mechanism to some type of naturally occurring electrolysis?
There are photos of gold in leaves on-line. The gold on tree roots is reliable, specimens from the 1800s are in the British Museum.

Yes, I have no problems with the research regarding those thanks goldierocks. And it does make sense. I was just responding to yet another comment earlier regarding the gold plated nail. I've heard it told ad nauseum in different forms- Gold nail in a mine, gold bolt left in a shaft, coin in a river, bullet casing etc etc. I just think people latch onto these things too readily with regard to their belief of photos existing. I'm still on board with gold precipitation, and yes I have seen those photos of the gold in leaves, and it is amazing stuff.
 
There is a quite beautiful one too of a fine gold line following the spiral of a fossilized sea shell.
 
malri_au said:
example of one of the things Goldierocks has said that I disagree with,'ignore dykes/dikes'.
???? lost me there. I did a thesis on gold in dykes.

This might interest some. Mel also did the work on gold in calcrete (used to find the Challenger gold deposit in South Australia)

https://youtu.be/Mp4Umeduhuw
 
Awesome thanks goldierocks :Y: That's exactly how I understood the process to work "like a Hydraulic pump", and when you see a felled Mountain Ash, River Red Gum, Ironbark etc., it's amazing when you see the sap veins running up through the tree trunk and think that it had to overcome gravity and pull that thick viscous sap all the way up to the top of the tree and its leaves, it would have no problem at all in carrying gold particles with it. And, something I hadn't considered until viewing that video and it's graphics is of course those leaves then eventually fall onto the ground and release the gold, and then potentially go on to contribute to various other cycles on the forest floor, such as gold eating bacteria, fungi, interaction with near-surface ironstone etc etc. Thanks for that
 
csiro...yeah not exactly my favourite people considering when I contacted them they didn't/couldn't/wouldn't deal with me.

yes,i read their gold in gum tree leaves stories when they where first published.

a few reasons i don't like the csiro.

the dyke thing,i remember reading a convo on here about beeping and where to look for gold and you'd said don't worry about dykes.i remember it because i was tempted to post but didn't.

interesting you did thesis on dykes,there's not a lot of discussion on them,would be keen to read it some time.(amherst camp out was near one).

i try to respect others,but when they throw disrespect,i tend to throw it back.

did you see the csiro's recent fungal gold research?

if i said i'd discovered it way before they did,i just didn't publicize it you'd call a bloke crazy right?

https://www.csiro.au/en/News/News-releases/2019/Gold-coated-fungi-are-the-new-gold-diggers
 
1572700758_csiro_poo.jpg
 
malri_au said:
csiro...yeah not exactly my favourite people considering when I contacted them they didn't/couldn't/wouldn't deal with me.

yes,i read their gold in gum tree leaves stories when they where first published.

a few reasons i don't like the csiro.

the dyke thing,i remember reading a convo on here about beeping and where to look for gold and you'd said don't worry about dykes.i remember it because i was tempted to post but didn't.

interesting you did thesis on dykes,there's not a lot of discussion on them,would be keen to read it some time.(amherst camp out was near one).

i try to respect others,but when they throw disrespect,i tend to throw it back.

did you see the csiro's recent fungal gold research?

if i said i'd discovered it way before they did,i just didn't publicize it you'd call a bloke crazy right?

https://www.csiro.au/en/News/News-releases/2019/Gold-coated-fungi-are-the-new-gold-diggers
I definitely would not have said that gold was not a place to look for gold - there have been million ounce orebodies found in them all around the world, including in Victoria. And as I said I have written on them (researched them in detail). Either I explained something poorly, or you misread, or possibly it was in the context of a specific area (eg in some areas the dykes are later than the gold - so not a good place in themselves to look for gold). Yes, Amherst, some of the bigger producers at Maryborough, Walhalla (Long Tunnel/Cohens), Woods point (Morning Star, A1), even Diamond Creek and Reedy Creek-Clonbinane near Melbourne and part of the ore at Fosterville, have gold ore bodies in the dykes (much more so than outside the dykes in the adjacent sedimentary rocks). In fact, more than one in five of the gold-antimony ore bodies north of Melbourne are mostly confined to dykes.

Thinking back, I suspect it might have been a discussion of Bendigo, where the "lamprophyre" (monchiquite) dykes that cut through the anticlines in the gold mines are more than 200 million years younger than the gold deposits.
 
malri_au said:
probably,was only speed reading and can remember it sticking in my head.no offence intended,it was more about the knight shiz.lol.
No probs - these are all gold veins in dykes from Victoria (mostly Walhalla-Woods Point):

https://www.researchgate.net/profil...its-a-Sigmoidal-en-chelon-veins-in-Eureka.png

https://www.researchgate.net/profil...-a-Typical-interbedded-sandstone-and_Q320.jpg

https://www.researchgate.net/profil...heared-dyke-margin-Dyke-is-pale-rock_Q320.jpg
 
In this photo you can see a black dyke of monchiquite ("lava dyke" or "lamprophyre dyke") cutting through an earlier gold-bearing quartz vein, Central Deborah mine, Bendigo. So although the dykes in the previous photos that I posted would be good to chase for gold, this type would not be as it is hundreds of millions of years younger than the gold-bearing quartz vein. This is a very narrow dyke but they are typically much thicker (but it is easier to see the cross-cutting relationship with this narrow dyke photo).

https://ic.pics.livejournal.com/monissaw/4489254/1323341/1323341_original.jpg
 
it's the easy way i explain a dyke to someone,fault that has had volcanic/magmatic contact.diamond dyke association is something else again.
 
Well , it's all got me stuffed. So many different age periods. Its very interesting to me and ive always been fascinated with it. Wish I had a rock sampling tool that read out instant information.

I know a spot where there's plenty of iron stone, dykes, and white clay all not far from each other.
Love exploring around that area.
 
They are great photos goldierocks, sorry if I sounded like a Doubting Thomas in an earlier post. I re-read the thread this morning to see where the wheels fell off with Malri and I, and I can see where I seemingly conflated the Bullet shell, nail, coin, bolt faves with your statement regarding the gold on roots. My apologies to Malri too.

With regard to Dykes and their age relative to gold deposition, there seems to be some confusion about this. Near McIntyre at Longbush for example, I have heard people refer to a geological feature there as both a Granitic Dyke, and a Volcano. Firstly, which would be the correct term? Secondly, I thought the granite outcrops that we see throughout the golden triangle & Kooyoora areas of Rheola, Dunolly, Kingower and surrounds, were a geological feature which came much later than gold?

I think from my own background (one of my quals is in Adult Education), I understand that people learn in many different ways. Verbal, Visual, demonstration, role-play, study & exams etc. Personally I am very much a visual person, and your Dyke photos are brilliant.- Thanks :perfect:
 
Deepseeker said:
They are great photos goldierocks, sorry if I sounded like a Doubting Thomas in an earlier post. I re-read the thread this morning to see where the wheels fell off with Malri and I, and I can see where I seemingly conflated the Bullet shell, nail, coin, bolt faves with your statement regarding the gold on roots. My apologies to Malri too.

With regard to Dykes and their age relative to gold deposition, there seems to be some confusion about this. Near McIntyre at Longbush for example, I have heard people refer to a geological feature there as both a Granitic Dyke, and a Volcano. Firstly, which would be the correct term? Secondly, I thought the granite outcrops that we see throughout the golden triangle & Kooyoora areas of Rheola, Dunolly, Kingower and surrounds, were a geological feature which came much later than gold?

I think from my own background (one of my quals is in Adult Education), I understand that people learn in many different ways. Verbal, Visual, demonstration, role-play, study & exams etc. Personally I am very much a visual person, and your Dyke photos are brilliant.- Thanks :perfect:
I tend to be more visual as well - a case of a picture worth a thousand words. But as a former lecturer I was aware of the need to cater for all. However geological relationships are often more immediately clearer with images.

At McIntyre there are various dykes, so I need to know which one you are referring to. The one that I know on the hill west of the road (where in situ nuggets were found) is "granitic" (I think strictly it was a diorite or granodiorite). A similar diorite occurs a few tens of metres at most west of the fence behind the church at Rheola/Berlin (west of the "potato patch").

Most granite are later than gold in central Victoria. There are some earlier than gold at Mafeking in the Grampians (they are unusual from memory, alkali granites with sodium amphiboles I think). However dykes like the one behind the church are often called "granites" because they are light in colour, but are an older generation of dykes more akin to diorite. There is also a generation of gold in central Victoria, more restricted in occurrence and often with gold-antimony mineralisation, that post-dates the main gold mineralisation in the region, and which cuts and mineralises dykes that are truly granitic in composition (some would call them quartz porphyry dykes). Although more geographically restricted they are still important in places (the Coimadai antimony-gold mine - and I suspect the mineralised dykes in the northeast of the Fosterville mine area - where antimony is also present). I have not seen this phase of gold mineralisation west of the Avoca Fault (which is just east of Avoca) but it extends to a few km west of Woods Point and includes the Costerfield mine, another important gold mine operating at present) and minor mines like Nagambie and Diamond Creek. These dykes are mostly Late Devonian.

So there may be as many as three generations of gold mineralisation in central Victoria. Silurian, Early Devonian (eg Rheola, Maryborough) and Late Devonian. I don't know of any dykes that are syn or pre the oldest of these (Silurian, eg Bendigo, Ballarat). However minor Late Devonian gold-antimony mineralisation is also present at Ballarat and Bendigo. At Percydale, Fiddlers Reef both cuts an early dyke and is itself cut by a later dyke.
 
Deepseeker said:
They are great photos goldierocks, sorry if I sounded like a Doubting Thomas in an earlier post. I re-read the thread this morning to see where the wheels fell off with Malri and I, and I can see where I seemingly conflated the Bullet shell, nail, coin, bolt faves with your statement regarding the gold on roots. My apologies to Malri too.

With regard to Dykes and their age relative to gold deposition, there seems to be some confusion about this. Near McIntyre at Longbush for example, I have heard people refer to a geological feature there as both a Granitic Dyke, and a Volcano. Firstly, which would be the correct term? Secondly, I thought the granite outcrops that we see throughout the golden triangle & Kooyoora areas of Rheola, Dunolly, Kingower and surrounds, were a geological feature which came much later than gold?

I think from my own background (one of my quals is in Adult Education), I understand that people learn in many different ways. Verbal, Visual, demonstration, role-play, study & exams etc. Personally I am very much a visual person, and your Dyke photos are brilliant.- Thanks :perfect:
I'm a bit doubtful about some of those nail etc stories but I did not want to go there. It does happen with some metals (eg in copper mines), but it would be an unusual situation for gold and gold is just in too low a concentration to do it in an actual flowing stream.
 
goldierocks said:
I'm a bit doubtful about some of those nail etc stories but I did not want to go there. It does happen with some metals (eg in copper mines), but it would be an unusual situation for gold and gold is just in too low a concentration to do it in an actual flowing stream.

As am I,i've never sided with the nail in this thread! ;)
 

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