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LBD  
#1 Posted : Saturday, 7 July 2012 5:21:14 a.m.(UTC)
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Because gold purity varies around the country, I would be interested to know what assay values have been found.

To kick it off, I took some gold from near Murchison and had it assayed at work today...

Au-94.609%,
Ag-4.073%,
Impurities-1.318%

How does that compare with other findings?
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gavin  
#2 Posted : Thursday, 2 August 2012 12:50:00 a.m.(UTC)
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I'm actually curious about this also... anyone know / have any numbers to share?
kiwijw  
#3 Posted : Thursday, 2 August 2012 9:22:36 a.m.(UTC)
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Hi guys, I dont have any hard & fast figures but hear that the Arrow & Shotover gold is generally around 92 - 96% pure & other areas around central as high as 98%. I believe that the finer alluvial gold is the higher its purity. This is due to the fact that becase the gold particles are so small they have had a lot of natural weathering, beating & effects of natural ground/water/plant acids that have helped leach out the impurities. The gold being small the acids are able to deal to the whole mass of the gold over time giving it its high purity.
Hard rock gold of the geothermal & hydrothermal type:ie Coromandel, has a very high silver content & other base metals, lead ,zinc copper etc. It was these other impurities that made these mines non profitable in the early days as the known processes of the day couldnt geal with them, & they knew they were lossing more gold than they were saving. How frustrating for them until the cyanide process was disscovered. This revolutionised these mining areas. In fact the Martha mine in Waihi is really a silver mine with production being 80 - 90% silver & gold only 10 - 20% . The gold & silver being chemicely locked in to the ore & not raw native gold/silver that you can see. It is so fine that you cant see it with the nacked eye. Hence the chemical cyanide process to extract it. All the southern Coro mines were of this nature, Waihi, Golden Cross, Waitakauri, Karangahake, Komata, Maratoto, Neavesville. Thames & Coromandel township area & the firth of Thames costal side had some filthy rich gold bonanza zones where there was way more gold than rock. Just a massive load of gold that would jamb up the stampers & they would have to stop the machinery & literaly scrape the gold off the stampers with the rock crushings squashed up in amongst the raw gold. Woulgnt you hate to have to do that LOL :)

JW :)
thanks 1 user thanked kiwijw for this useful post.
gavin on 2/08/2012(UTC)
kiwikeith  
#4 Posted : Thursday, 2 August 2012 10:08:20 a.m.(UTC)
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up on my claim i run at an average of 96%
thanks 1 user thanked kiwikeith for this useful post.
gavin on 2/08/2012(UTC)
treeman  
#5 Posted : Thursday, 2 August 2012 11:53:49 a.m.(UTC)
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our Claim
fine gold 95.2%
nuggets 92.5%


cheers
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gavin on 2/08/2012(UTC)
LBD  
#6 Posted : Thursday, 2 August 2012 12:04:42 p.m.(UTC)
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Originally Posted by: treeman Go to Quoted Post
our Claim
fine gold 95.2%
nuggets 92.5%


Interesting...I would have thought that because the fine gold is the result of nuggets being worn down in a river bed, that the composition would have been the same ...
gavin  
#7 Posted : Thursday, 2 August 2012 12:17:57 p.m.(UTC)
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Cheers guys - very much appreciated! :)
1864hatter  
#8 Posted : Thursday, 2 August 2012 12:52:02 p.m.(UTC)
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Frow the 2 guys that I know that have had gold from the Wakamarina assayed they average around 95%
And now....On sandy beaches and muddy soil, rings and coins await my coil!
oroplata  
#9 Posted : Thursday, 2 August 2012 1:52:25 p.m.(UTC)
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Originally Posted by: kiwijw Go to Quoted Post
Just a massive load of gold that would jamb up the stampers & they would have to stop the machinery & literaly scrape the gold off the stampers with the rock crushings squashed up in amongst the raw gold. Woulgnt you hate to have to do that LOL :)


Yeah, that would be SUCH a bummer.

oroplata  
#10 Posted : Thursday, 2 August 2012 1:53:29 p.m.(UTC)
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Originally Posted by: treeman Go to Quoted Post

nuggets 92.5%


Sterling gold!

kiwijw  
#11 Posted : Thursday, 2 August 2012 8:58:12 p.m.(UTC)
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Originally Posted by: LBD Go to Quoted Post
Originally Posted by: treeman Go to Quoted Post
our Claim
fine gold 95.2%
nuggets 92.5%


Interesting...I would have thought that because the fine gold is the result of nuggets being worn down in a river bed, that the composition would have been the same ...


If you read my first post on finer gold having a higher purity you will see the reason.....generally.

JW :)

treeman  
#12 Posted : Thursday, 2 August 2012 11:16:55 p.m.(UTC)
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Not if the fine gold has traveled and came form a different formation than the nuggets, ie the laying down from two different ice ages into the same area or one traveling fro a different area.

cheers
gavin  
#13 Posted : Friday, 3 August 2012 7:59:12 p.m.(UTC)
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Interesting... a gold buyer informs me that "normally 18ct/75%+ is typical for NZ". I guess I'm being told worse case scenario here as seems a bit low from other peoples reports! But there is a + in there I guess ;)
LBD  
#14 Posted : Friday, 3 August 2012 11:02:41 p.m.(UTC)
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Originally Posted by: gavin Go to Quoted Post
Interesting... a gold buyer informs me that "normally 18ct/75%+ is typical for NZ". I guess I'm being told worse case scenario here as seems a bit low from other peoples reports! But there is a + in there I guess ;)


I would say if you are being offered a price that matches 75% purity for NZ aluvial....then there is a good chance you are being had. Suggest you get an independant analysis done...before selling any qty to that buyer.

gavin  
#15 Posted : Saturday, 4 August 2012 12:00:52 a.m.(UTC)
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Originally Posted by: LBD Go to Quoted Post
Originally Posted by: gavin Go to Quoted Post
Interesting... a gold buyer informs me that "normally 18ct/75%+ is typical for NZ". I guess I'm being told worse case scenario here as seems a bit low from other peoples reports! But there is a + in there I guess ;)


I would say if you are being offered a price that matches 75% purity for NZ aluvial....then there is a good chance you are being had. Suggest you get an independant analysis done...before selling any qty to that buyer.


Yes, I figured I'd get an assay done as once passed over there's not a lot of come back. Figured 75% was on the very low end!

kiwijw  
#16 Posted : Saturday, 4 August 2012 11:53:35 a.m.(UTC)
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Originally Posted by: gavin Go to Quoted Post
Interesting... a gold buyer informs me that "normally 18ct/75%+ is typical for NZ". I guess I'm being told worse case scenario here as seems a bit low from other peoples reports! But there is a + in there I guess ;)


Take your car to a car dealer & see what he will give you for it & then if you sell it to him go back & see how much he is on selling it for. Gold buyer is no different. They need to make their money too. The easy money, like any middle man, as they arent the ones out there up to their nuts or even worse in freezing cold water doing the hard yards.

JW :)

treeman  
#17 Posted : Saturday, 4 August 2012 1:14:34 p.m.(UTC)
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When you sell gold the age old facts that come back are purity and melt loss
the last two sells, purity was about 94% one sell had 5.6% melt loss and the other had 11% melt lose.
the second one I did not clean my gold that well due to the fact I was getting fed up with the job.
also nuggets have a greater melt loss than real fine gold.

so I was paid 88.4% on one and 83% on the other. and the price per ounce was $2016 and $2085.

If you are getting below 85% for good clean gold then you are being ripped or you are selling to a middle man ( a shark buying and on selling )
as said before they have to make money as well.

The best option is clean it real good and or melt it down yourself and then send to one of the major buyers.
with lots greater than an ounce the bigger the lot the better, assay is about $70, transaction fee I pay is $7.50 per ounce.
at the end of the day you can sell it to anyone and the price you get is up to you to accept.

thanks 2 users thanked treeman for this useful post.
gavin on 4/08/2012(UTC), kiwijw on 5/08/2012(UTC)
gavin  
#18 Posted : Saturday, 4 August 2012 10:31:46 p.m.(UTC)
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@kiwijw - No worries, I understand gold dealers need to make their money too. This one I had asked what price below the spot price they buy for, this is what I consider a fair and transparent cost (based on difference to spot price). The purity of gold is not something I want down adjusting in the buyers favour along with the value below spot ;) He may be completely honest and trying to lower my expectations based on the worst case he's seen, perhaps based on badly cleaned gold in case I'm crap at cleaning gold. Who knows - he didn't provide any detail of why as low as 75%. I would imagine he'd realise this sounded low and provide some justification. But it does raise a few doubts in the back of your mind when it would be the first time dealing with the company. Not planning on selling any - just wanted to know what's a likely price in case I fall on hard times. It's too pretty to sell - my preciousessss! :P

@treeman - Thanks for the useful info - didn't realise there was melt lose to consider. Much appreciated! Always wondered if you got the full 100% back after melting, figured a very minor must get lost in the process.
kiwijw  
#19 Posted : Sunday, 5 August 2012 8:07:22 a.m.(UTC)
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Originally Posted by: treeman Go to Quoted Post
When you sell gold the age old facts that come back are purity and melt loss
the last two sells, purity was about 94% one sell had 5.6% melt loss and the other had 11% melt lose.
the second one I did not clean my gold that well due to the fact I was getting fed up with the job.
also nuggets have a greater melt loss than real fine gold.

so I was paid 88.4% on one and 83% on the other. and the price per ounce was $2016 and $2085.

If you are getting below 85% for good clean gold then you are being ripped or you are selling to a middle man ( a shark buying and on selling )
as said before they have to make money as well.

The best option is clean it real good and or melt it down yourself and then send to one of the major buyers.
with lots greater than an ounce the bigger the lot the better, assay is about $70, transaction fee I pay is $7.50 per ounce.
at the end of the day you can sell it to anyone and the price you get is up to you to accept.



Hi there Treeman, Yes....very good point about the dreaded melt loss. 11% seems awful high. Just out of curiosity, where does the melt loss go? Does it just evapourate, fall on the floor or into a pocket LOL :) or is it absorbed by the crucible to be crushed & retrieved later & put in the pocket. Do you get paid out on other metals present like the silver/copper content or are these a perk for the refiner??

Cheers

JW :)
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