glot
Gold Digger
Posts: 75 
|
Post by glot on Oct 7, 2014 18:27:47 GMT 10
How small a bit of gold can the average person see in good sunlight? What size are those pin pricks that you can just make out as gold? I read somewhere a good panner can only go down to 80 microns. The finest resolution my tape measure has is 1000 microns.
|
|
|
|
Post by Ric on Oct 7, 2014 18:41:01 GMT 10
Hmmmmmm, Never thought about it before. If I can't see it I wont miss it
|
|
|
|
Post by shivan on Oct 7, 2014 20:59:28 GMT 10
The most i have ever measured to is 100+ mesh screen size which is about 150- microns and that is getting very small, not sure if my eyes would be up to the challenge of 80 microns...
|
|
|
|
Post by Ric on Oct 7, 2014 22:19:23 GMT 10
Just having a read on measurements.(1000 microns = 1mm)so 100 microns = 0.1mm ( 1/10th millimeter) which should be easy enough to see with the naked eye.
I think a lot of the flood gold we get at Oallen would probably be smaller than 100 microns. I'm not sure how it could be measured except by using filter mesh of some type?
Cheers Ric
|
|
|
|
Post by shivan on Oct 8, 2014 18:42:35 GMT 10
I have not really thought about the micron size before, just did a quick google to try an convert the mesh to micron before. But the gold smaller than my smallest 100 mesh screen is getting around the silt particle size, visible but easily hidden with any crap in the water/pan
|
|
|
|
Post by danielkrupski on Oct 8, 2014 19:13:26 GMT 10
I'm sure micro gold is at oallen as there is in any gold stream but if you can't see it how do you get it? It would have to be smelting of sands or chemical extraction. I looked into it a while ago for the cost of smelting or using chemicals just throw another 10 to 20 shovels in the highbanker . After you say your done for the day I usaually throw another couple hundred more
|
|
|
|
Post by jeffu on Oct 8, 2014 19:36:17 GMT 10
The gold at Oallen is, for the most part, VERY fine, not sure I'd call it "micro" though. Most of it is fly dropping size but it's visible and plenty of it.
I don't use any chemical assistance to recover it. All the final concentrate gets brought home and run done a Miller table, almost 100% recovery, removes everything just leaving the superfine gold behind.
Shivan uses a blue bowl for his fine gold recovery. I've never seen anyone set one up as well as he does, Oallens' gold, probably greater then 99% recovery.
Have the right equipment and have it set up correctly and there's no need to use any chemicals at all.
|
|
|
|
Post by mushmouse on Oct 11, 2014 0:00:45 GMT 10
I had a fair bit of fine flour gold in the last batch. This stuff was super fine ( needed glasses to see ) - almost silt like and it always amazes me how it finds its way to the bottom of the pan with the others when panning off at home. I check the pan that I panned into and did not get any escape. It's surprising how something so tiny can be so heavy. Once its dried and put out under the magnifying lamp I use, those particles are much easier to view and brush away from silt grit. The light on the lamp give it a shine and it's always better to have other overhead or ambient lights off.
Once magnified it increases to fly poo size - so you can imagine how small this stuff is. Still good pass time cleaning it tho..
|
|
|
|
Post by Ric on Oct 14, 2014 17:54:27 GMT 10
|
|
|
|
Post by hunting the yellow on Oct 16, 2014 18:27:02 GMT 10
|
|
|
|
Post by mushmouse on Oct 16, 2014 23:51:46 GMT 10
That's a great photo. It's interesting to see such a small specimen on it's host rock and to see the type of quartz it is. What is that reddish colour through it - is it some sort of coppery sulphide? I like to check out quartz and look for indicators and try and learn more.
|
|
|
|
Post by jeffu on Oct 17, 2014 6:31:16 GMT 10
Being in this stupid industry (Printing) I know that 140mesh is very close in size to the thickness of a sheet of standard 80gsm paper (0.1mm). That is quite visible. So for all of you that want to know how big you Oallen gold is, just take a sheet of paper with you.  |
|
|
|
Post by hunting the yellow on Oct 18, 2014 21:59:55 GMT 10
That's a great photo. It's interesting to see such a small specimen on it's host rock and to see the type of quartz it is. What is that reddish colour through it - is it some sort of coppery sulphide? I like to check out quartz and look for indicators and try and learn more. yeah its iron oxide the pyrites in the rock oxidizing with the natural elements like air water other minerals in the rock reacting to it chemically |
|
