999.50 degrade to 995 kilo bar we are losing gold

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sasi4gold

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snoman701 said:
What is your rinsing process? Excess chlorides can cause volatilization of gold in the melting process. When the gold is melted in a silica or fire clay dish, do you see a pronounced purple stain on the dish?


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yes we keep monitoring rinsing process make sure no acidic then will send to smelters
thanks
sasi
 

nickvc

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sasi4gold said:
nickvc said:
Does the weight of refined powder match the weight of the melts as powder can produce losses if it’s not fully dry or is not rinsed properly to rid it of acids that can react and cause losses in the melting process.
firstly we melt powder in to large bars in house refinery smelting room , in this section any losses it will consider as refinery losses. our issues refined bars again convert to kilo bar another department, we carefully weighed and assayed
thanks
sasi

This makes no sense if you have a known assayed bar that is then refined again and then melt the powder for kilo bars there should be minimal losses but you will lose some depending on the processes you use simply by having filters with gold still in them, solutions not fully precipitated or settled small loses when pouring gold to the floor.
I would suggest a search through any process to ensure your missing gold is not tied up there to start failing that the only other reasons for the losses I can see is theft , bad accounting or bad assays.
 

sasi4gold

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nickvc said:
sasi4gold said:
nickvc said:
Does the weight of refined powder match the weight of the melts as powder can produce losses if it’s not fully dry or is not rinsed properly to rid it of acids that can react and cause losses in the melting process.
firstly we melt powder in to large bars in house refinery smelting room , in this section any losses it will consider as refinery losses. our issues refined bars again convert to kilo bar another department, we carefully weighed and assayed
thanks
sasi

This makes no sense if you have a known assayed bar that is then refined again and then melt the powder for kilo bars there should be minimal losses but you will lose some depending on the processes you use simply by having filters with gold still in them, solutions not fully precipitated or settled small loses when pouring gold to the floor.
I would suggest a search through any process to ensure your missing gold is not tied up there to start failing that the only other reasons for the losses I can see is theft , bad accounting or bad assays.
nickvc
hi brother thanks for your valid comment , you did not understand our problem because i did not explained you
properly .
our issue not in refinery.
e.g.
scarp gold 100 kg send to refinery 875 purity , chemically refined powder melted and get 87 kilo gram
forget 0.5 kilo it will be recover by our team.

87 kilo large bars dip sample assayed 999.50 let say 8 x 10 kilo - 1 x 7 kilo
87 kilo will move to another department
87 kilo poured as grains losses may be 10 gram its no issue recover latter
again all the grains will make kilo bars , in this step we are losing gold
please do not include refinery losses here . That is different recovery job, we are expert on it.
sometime we produces 999.9 and making kilo bars , we do not face losses anywhere
sometime third party gold 995 making kilo bars very less losses ie 10g recover latter.
i hope i explained right manner
thanks
sasi
 

nickvc

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If you are losing gold in the grain to kilo bar process then theft seems the logical reason as there will be no melt loss when melting fine gold metal.
I think 4metals has before said you need constant accountability in all departments of a refinery that way theft is nearly impossible and you know where and how losses are incurred and the way to recover them later which you seem to have in place, as stated above theft seems the only way losses such as these can occur.
 

snoman701

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I am having a hard time understanding, as I don’t think English is your first language.

But is there a possibility iridium is causing this? It will survive the fire assay.


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sasi4gold

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nickvc said:
If you are losing gold in the grain to kilo bar process then theft seems the logical reason as there will be no melt loss when melting fine gold metal.
I think 4metals has before said you need constant accountability in all departments of a refinery that way theft is nearly impossible and you know where and how losses are incurred and the way to recover them later which you seem to have in place, as stated above theft seems the only way losses such as these can occur.
ok dude today onwards will keep eyes on specific area
thanks a lot all experts who respond my posts
sasi
 

sasi4gold

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snoman701 said:
I am having a hard time understanding, as I don’t think English is your first language.

But is there a possibility iridium is causing this? It will survive the fire assay.


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noted will keep moniter will do xrf each and every steps
thanks
sasi
 

Lou

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Remember, in precious metals only two loss mechanisms:

Theft by incompetence or theft by deception.


In this case, it is someone pulling the the old switch the gold for silver trick.

1. I would suggest you pour and fabricate the gold bar yourself, unannounced, alone.
2. VERY CAREFULLY LOOK AT YOUR GRAINS before doing so. Be sure the assay on those grains is available and representative--one of your employees could have pulled out 1/2 kg or so of gold when the 87 kilo was to be poured as grains. He melted 8 X 10 kilograms that were dip sample assayed then put in maybe only 6 and 1/2 kilograms. That right there is a weak spot in your inventory control.

Always ask: much do my bars weigh, and how much silver do my bars have? Mass will never balance perfectly, but damn close in practice.

If it's NOT theft/intentional contamination, you must rule out accidental gold grain contamination. If the assay light on gold, then so too is the melt. You are adding more gold than you really are which means either gold grains contaminated/adulterated or have foreign material/excess moisture (you sure your grain is spherical? you should see no steam!)

The grains may be not properly dry, the grains may not be completely spherical, and most importantly, some joker may have put a bunch of borax in the crucible, or is using a new(er) fresh silicon carbide crucible and the glaze is getting mixed in with the gold grain.

On large grain lots, it's not uncommon to see some sort of flux contamination in the grain if workers were mistakenly/foolishly adding it.


There should be no incentive to use iridium (unless gotten artisanal) as it costs as much as gold and is far less available.
 

nickvc

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One way to stop any theft is to have one or two people only who can weigh out the grain and add the silver and remove all scales from susceptible areas, if you do this it should prove whether you are been robbed or the loss is explainable in some other way which I now highly doubt.
Unfortunately theft is a real problem when handling volumes of precious metals, employees see millions of dollars worth of gold and fail to realize that the profit the owners take can be a very small amount of that volume.
 

snoman701

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Lou said:
There should be no incentive to use iridium (unless gotten artisanal) as it costs as much as gold and is far less available.

Not if the thief has to source the iridium externally...however...

I was thinking more along the lines of, if they are processing 100 kg lots, they are probably getting iridium in the chlorides, albeit in small amounts.

However, it is my guess that those chlorides are a lot less scrutinized in terms of their value, and that the people trusted to handle those, are greater than the people trusted to handle the raw metal.

So redirecting a few ounces of what they thought was silver chloride, replacing with actual silver chloride, sourced externally, then moving the iridium to the gold....the mass balance works.

Until you discover that your gold is short.

Like I said, I was having trouble understanding the original posters process, and where the gold came up missing. Nothing against the original poster, as their english is very good, I'm just very dense. I seem to write as if english is a secondary language for me as well. I just wish I knew what my primary language is. :lol:
 

sasi4gold

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nickvc , lou , snoman701
Today i am making 885 to 999.9 kilo bars , i am sure i will not get losses in my refinery or smelting department.
i have tested many times 999.9 not give any problem
next two days i will make 999.50
i will consider all your comments and update you !
Note ; theft is very very rare
some scientific reason behind in this issue let us see
thanks
sasi
 

nickvc

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Make up several batches of the 999.5 bars and have them melt them in front of you if no losses then you know the answer...
 

sasi4gold

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fresh silicon carbide crucible and the glaze is getting mixed in with the gold grain.
from the begining i have doubt - semi washed refined powder , pickup crucible material in first step , those bars re-melt for convert to grains , finaly crucible materials are disappear is it possible ?
what is the right temperature to make kilo bar ? our smelting guys keep 1200 degree
 

Lou

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1200 is probably more than hot enough.

I cast large gold bars (>200 oz) at 1120. Never had a fluidity issue.
 

snoman701

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sasi4gold said:
fresh silicon carbide crucible and the glaze is getting mixed in with the gold grain.
from the begining i have doubt - semi washed refined powder , pickup crucible material in first step , those bars re-melt for convert to grains , finaly crucible materials are disappear is it possible ?
what is the right temperature to make kilo bar ? our smelting guys keep 1200 degree

The crucible will get consistently thinner and lighter, but this material should end up in the slags, or gas off as carbon dioxide. To my knowledge, the morgan crucibles aren't much more than silica, carbon (graphite & carbon from silicon carbide), pine tar, and possibly a little alumina to hold it all together. In other words, nothing that is going to end up in your gold.
 

sasi4gold

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snoman701 thank you ,
1) what is exact temperature for making kilo bar ?
2) for each each kilo we prepare the grains 1000.2g , for example if you make 10 kilo
end of the melting we should get - 10000.8 g . while we melt third party ( client ) gold we are getting
right result. while we produce kilo bar from our refined gold , we are getting 10000.3 or less than that means losses. while we produce 999.9 kilo bar also right result. whenever i want to degrade 999.50 to 995 losing gold.
if i make 10 x 1 = 10 kilo bar , i am losing 7 gram silver .same furnace which we use for gold kilo bars.
 

goldenchild

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I could see losses if going from sponge to grains. But from grains to bars the loses should be almost negligible. I'm gonna go with theft on this one.
 

sasi4gold

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goldenchild said:
I could see losses if going from sponge to grains. But from grains to bars the loses should be almost negligible. I'm gonna go with theft on this one.
noted thanks
 
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