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Gold Prospecting e-News, Issue #066 - Primary Secondary Gold from a 8 Ounce Patch
October 12, 2018
Primary or Secondary Gold Where Did it come From?
Table Of Contents
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Gold Prospecting Seminars Finished for 2018Gidday All,
The Gold Prospecting Seminars have finished for 2018 - The Next Seminars will be in 2019
Due to other commitments and issues we were unable to conduct any more gold Prospecting Seminars in 2018.
Due to many people requesting Seminars, particularly from Overseas, we will be running our Gold Prospecting Seminars in Cue again in 2019.
We will send out a newsletter with the details in late December 2018 or early January 2019.
Gold Prospecting WA Facebook
The Facebook page has grown significantly since we started it a few years ago and it has sorta taken on a life of its own.
In the next few weeks we will be adding some capability to it which will enable responses to new readers based on questions that are regularly asked of us.
This will free up some time for us in individually creating and sending replies to questions, especially from new readers.
Gold Prospecting WA Facebook Page
Primary or Secondary Gold in an 8 ounce patch
Congratulations to one of our seminar people who found 8 ounces of gold recently.
He asked me a question about the gold and wanted to know if there was any more gold based on the information he gave me.
That is always difficult to answer when you do not know the location, geology or topography of the area.
Nevertheless I attempted to help by talking about primary and secondary gold formation and asking him to put his thinking cap on based on that answer.
Here is the answer in brief.
"The gold looks like secondary gold formed in Laterite, (ferricrete - iron based) or Silcrete, as this is the gold formed by chemical weathering of the ground as the gold (and other minerals which the exception of those that are resistant to chemical weathering such as iron and aluminium) are taken into solution and transported down to the water table.
Later gold nuggets can re-form in the soil profile and close to the surface due to a change in the chemical content of the water such as with rainfall diluting it and causing precipitation of minerals like gold.
This precipitation and stripping of the minerals forms a very hard cap and the soil profile under it is light coloured stripped and devoid of minerals this ranges down then to the original bedrock - whatever that is.
Usually these extremely hard caps are formed on valley floors or the minerals are transported and formed in areas like saltlakes originally.
Then later there is secondary weathering process and laterite capped hills and mesas form when the original valley floors is eroded away.
You would have seen this formation on hills with the hard capped laterite layer ranging down to a pale soil that is stripped of minerals and then down to the mottled rock and bedrock.
Driving out of Cue Northwards this profile is very obvious and is called an inverted topography.
The point is that there must be a primary source somewhere to form the gold in this manner.
That may be below the gold you have found, upstream or uphill from where you found the gold, otherwise the original source may be a secondary deposit that has been carried in during an old Geological age (a paleo deposit in an old salt lake or stream bed) and the secondary process outlined above has taken place.
I would be thinking that there will be more gold in the hard capped laterite layer or at the base of it and possibly a primary source in the the area either underneath or upstream or uphill from the place where you are finding the gold.
Is there some gold mines up hill from the spot?"
Later he replied that there was some old gold mines on the side of hill up from where he found the gold in laterite.
Previous and Free Training on Where to Find Gold In WA
This was also explored in a previous newsletter ("Where Can I find Gold In WA") with a video which was released prior to the online GeoMap Training Website and it is on this page if you want to review it
Those videos are on the GeoMap Online Training Website and you can sign up for the free training there to see the video on "Where is the Gold in West Australia" GeoMap Training - Link to Training Including Free Training
More on the Pilbara Conglomerate Gold
This was originally discussed in a newsletter issue #59 here is the link if you missed it:
And here is the link to the new article.
A Refresher on What This Information on Conglomerate Gold Means to you.
What it means is that with access to Geomap, Tengraph Web that sort of information it provides valuable intelligence of the types of geology and structures you should be targetting in the areas involved.
That way you will not waste your time going to barren areas.
Its a simple process and very effective in enabling you to find new gold localities yourself.
Safety In Prospecting in WA
There has been a spate of missing persons in the Goldfields this year and this was discussed at the APLA AGM in September this year.
I (Bill) wrote a page for APLA Members which is also available to the public even if you are not a member of APLA.
Here is a link to that page, It has a checklist and Leonora Police Contact form that you can use. APLA Page on Safety in the Bush.
This is a subject we deal with in our Gold Prospecting WA newsletters and talk about in our Seminars.
It never ceases to amaze us that people will spend thousands of dollars on gear and offroad vehicles but not a few hundred on safety or communication deviceslike;
You can buy these items at your local Prospecting or Metal Detecting Store so get one now, learn how to use it and use it!
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Department of Mines PublicationsLink to the Department of Mines (DMIRS) Publications
Here is a link to some of the publications available through the Department of Mines (DMIRS) website - sign up to them if you have an interest in the subjects.
Geological Field Notes quarterly newsletter published by the Geological Survey of Western Australia (GSWA).
From the DMIP Website "The newsletter provides regular updates to the State’s exploration industry and other geoscientists about GSWA’s latest work, programs, products and services."
Geological Survey eNewsletter and Back Issues Page
From the DMIRS Website The Geological Survey of Western Australia (GSWA) eNewsletter is an online periodical newsletter that contains information on geophysical data releases, workshops, field trips, events, as well as latest releases of maps, books and digital data packages. GSWA Newsletter sign up page.
There is always a lot of valuable information provided in these newsletters.
Also remember that our webpage Geological Maps shows you how to access free Geological Maps and other valuable prospecting information from the DMIRS E bookshop.
Many of the publications are available in digital format for freely downloadable from that site.
Coming in the Next MonthFor the GeoMap Training site members (GeoMap Online Training and Tengraph Web Training) in the next two weeks.
Advanced GeoMap training pages.
APLA Open Day for Everyone
The Amalgamated Prospectors and Leasheolders Association Perth branch will hold an open day for the public again this year on24/11/2018 - this is a great opportunity to learn about Prospecting for Gold in WA.
Location - Duncraig Community Hall Cnr Marmion Ave and Warwick Rd.
The Open Day is free for everyone to learn about Prospecting in WA and about APLA.
Duncraig Community Hall Cnr Marmion Avenue and Warwick Rd. 10am to 3pm
I will be speaking at the Open Day and will provide an extra special offer for access to Online GeoMap Training for those that attend the APLA Open Day,
Reeds Prospecting are Moving.
Reeds Prospecting in Perth will be changing address and having a Sausage Sizzle on 20 October 2018.Reeds Prospecting Open Day
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See you in the Field and if we don't -
...may you find plenty of gold nuggets in 2018
Udo and Bill
Nobody gets ALL the gold. There’s still plenty left for you.
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