Welcome guest, is this your first visit?
Member
Discoveries
 
Results 1 to 7 of 7
  1. #1
    Cappy Z.

    Gold and Quartz geology

    It is no secret that veins of white quartz have gold seams. When the quartz was liquid as was the gold it was deposited into cracks and became veins once cooled and hardened. My question is, how did the gold coagulate in these specific amounts? Were the gold molecules 'attracted' to each other and 'melted' together? Since the gold in quartz model is so prevalent does the quartz have some ability to attract gold when molten? Kind of like a magic wand attracting the iron filings in that kids game? It seems that when liquid at high temperatures the quartz becomes a readily available boat to carry the gold until its cooled. I suppose I am wondering if this could be repeated in a controlled scientific experiment?


  2. # ADS
    Ads
    TreasureNet.com is the premier Treasure Hunting Forum on the internet. Registered Users do not see these ads. Please Register - It's Free!

  3. #2
    us
    Feb 2008
    SE Missouri
    garage sale oldie
    2,885
    692 times
    TH'ing, fishing, reading, cooking

    Re: Gold and Quartz geology

    am waiting to see what the answer is Cappy. It never ceases to amaze me how deposits occur. we have large seams of white clay that is perfect for firing, but how can it be so thick in one spot, & an inch away none. have you ever seen the books A Roadside Geology of - - - , WA, ID etc. they are great books. I found them quite informative, but just led to more questions. would love to be a professional student.
    dancing in the fire!

  4. #3
    Cappy Z.

    Re: Gold and Quartz geology

    Thanks for posting Mamabear. The reason I ask the question about repeating mother natures activity in the science lab is because I think if we ever find a way to extract gold from sea water, the formula if you will, starts and ends with reverse engineering. It is a known fact that gold is added to glass to give it a red color. Glass of course is not dissimilar to volcanic magma particularly quartz. It seems to reason that during the volcanic processes whereby magma is pushed under great pressure into fractured crevasses and gold comes along for the ride, the gold must be coming from underground seawater. Maybe some chemical property in the white quartz 'attracts' the gold. Also maybe the white quartz facilitates the clumping of gold atoms as an amalgam would. Hence attempts at reverse engineering in the lab might offer the Philosophers Stone up for grabs.

  5. #4
    us
    Nov 2005
    colorado
    Whites MXT
    93
    3 times
    All Types Of Treasure Hunting

    Re: Gold and Quartz geology

    Cappy,

    The primary deposition of gold and gold bearing minerals are hydrothermal in nature. This means that the Au is carried in a solution associated with volcanic activity. As the solution and the surrounding host rock begin to to cool the Au then precipitates in the host rock. There are phase diagrams that have been developed that show silica minerals (quartz and others) and gold are deposited/precipitated at nearly the same temperatures (if I remember correctly quartz is slightly higher in temp), thus the association of Au with quartz. Other than the temperature relationship, quartz does not "attract" gold. Of course there are exceptions to this but generally this is how Au is deposited in volcanic host rocks. Many times other minerals are associated with the hydrothermal deposition of gold including sulfides, tellurides etc.
    Another deposition process may be that a volcanic event occurs in existing rocks and forces gold bearing solutions into the cracks and fractures of the host rock creating vein structures in said host rock.
    It is then the erosion of these deposition processes by wind, water, ice etc. that remove and free the gold from the host rock and when liberated the gold is then found in placer deposits (where dredging and panning would occur).
    This is a very general explanation so hopefully someone else will chime in if you want a more in-depth answer. There are all sorts of geochemical/physics actions that complicate the gold deposition process.

    Hope this helps.
    3xflyfisher
    if not flyfishing - TH'ing, if not TH'ing - flyfishing
    Whites MXT

  6. #5
    Cappy Z.

    Re: Gold and Quartz geology

    Thanks 3xFlyfisher for posting. It seems that white quartz is the primary host rock for the gold when the temperature cools. I understand there are other rocks, but it seems white quartz has a greater claim on being found with gold. Also, I wonder how gold nuggets are formed in various sizes? Why one hears of 5 pound nuggets but most are pickers? I wonder what the geological processes were that allowed for a giant gold nugget to be formed. I sense there are clues here that would add to the understanding of how gold is formed and where it can be found. Recent articles I've read state on the ocean floors and continental shelves there are large concentrations of gold, not just dissolved in the water. Again, thanks for responding.

  7. #6
    se
    Sep 2006
    Sweden
    White's or Minelab
    3,753
    184 times
    All Types Of Treasure Hunting

    Re: Gold and Quartz geology

    The thing with quartz and hydrothermal actions is they can pass through much rocks and dissolve minerals from the surrounding rocks.
    As it then begins to cool it will deposit these minerals - which then occur in a more concentrated state then it did in the rocks it was dissolved from.
    Most of the time!

    As for the chemistry part, gold can occur as ions; Gold(I) and Gold(III) I think occur naturally. Not certain though.

    Often (mostly?) they tend to go attract Chloride - Gold Chloride is water soluble.

    As far has large nuggets are formed - that's still up for discussion I think.
    Logically there has to be enough space, time and of course gold (chloride) present to make a large nugget.
    That's my theory - A lot of gold has to crystallize out of solution and clump together.
    Geologists are gneiss, tuff, and a little wacke.

  8. #7
    us
    Nov 2005
    colorado
    Whites MXT
    93
    3 times
    All Types Of Treasure Hunting

    Re: Gold and Quartz geology

    I believe all nuggets are formed exclusively by the erosion of the original deposition of gold. Here in Colorado there have been many "nuggets" found that are are crystalline and very large (up to 8lbs if I remember correctly. These have been found more in alluvium or deposits that have not been transported, or transported far by water. Once the coarse gold is in a stream or river other erosional forces take over as the gold bounces and tumbles along the stream bed (think sand blasting but with water as the transport medium rather than compressed air), thus making coarse gold a nugget (rounded like landscaping river rock). Through this process a large crystalline nugget will break down into smaller pieces and become the pickers you mentioned and also the flour gold that many weekend prospectors recover. The closer to the source the coarser the gold is. Of course there are exceptions to this such as deposits in metamorphic rocks rather than volcanic rocks. In metamorphic situations while similar there are other forces/reactions taking place. I have a sample where the gold has precipitated onto various oxide and hydroxides of copper and while I am not sure, this may be a case of gold chloride precipitated the precious metal.

    As far as size, depending on the conditions at the time of the original deposit any thing or size is possible. There a many many variables involved and also volumes of research discussing these variables thus this discussion could go on indefinitely. Eucitizen is right though that depending on the chemistry involved with a particular volcanic event, the gold chlorides can and do greatly contribute to the primary deposition of Au. Eu also is correct in that depending on the actual conditions involved in a particular deposition event there can be a cycle or multiple cycles of deposition/dissolving of the gold concentrating it through these cycles.

    I think it appears that gold has an affinity for quartz since that is the type of specimens that most collectors prize, hence when found many are saved for the specimen value. In Nevada, many of the current large open pit mines operating show no or very little visible gold. It is microscopic and disseminated nearly equally through the host rock that is a nondescript tan/brown/gray (ugly!) rock, but can show high values of gold.

    I am sure you have heard of the "black smokers" that have been discovered on the ocean floor. These can and do deposit precious metals that if on the surface would be economical to mine. Also associated with the smokers are silver, copper, lead, zinc and a myriad of other metals. But due to the depths of these it is not economical to recover these values.

    Have a good'one,

    3xflyfisher

    if not flyfishing - TH'ing, if not TH'ing - flyfishing
    Whites MXT

 

 

Sponsors

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Search tags for this page

gold and quartz relationship

,
gold in white quartz
,
how to extract gold from quartz at home
,
how to find gold in quartz
,
quartz and gold relationship
,

quartz gold relationship

,
relationship between gold and quartz
,
whats the correlation relationship between gold and quartz
,
white quartz and gold
,
why are gold and quartz found together
Click on a term to search for related topics.
Powered by vBadvanced CMPS v4.1.3