# old slag



## Anonymous (Oct 13, 2010)

old slag, took some crushed it up and there is alot of silver looking metal i picked out about an ounce, tested it some bright red then yellow. i have crushed some and stuck it in nitric acid and it turned the acid a bright green color an there was a fluffy layer if the crushed junk. so from wat i read this stuff is probibly junk i should throw it away??? also having a problem, can't delete any post.


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## 4metals (Oct 13, 2010)

First and foremost, crush a sample and have it assayed. Then you know what you're looking for. Right now you haven't provided enough information for someone to tell you anything which you may find helpful.


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## Anonymous (Oct 13, 2010)

When u have this slag assayed professionaly do tell the assayer what it is and use two assayers. Also crush a representitive sample over the whole batch....chip off bits from numerous pieces to get a 500 gr sample, then split this in half.


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## Harold_V (Oct 14, 2010)

My personal opinion is that unless you can see prills in the slag, you shouldn't spend much time screwing with it. I expect that is not the case. 

Slag is not much different from an ore. If the value content is low, the cost of recovering is most likely to exceed the value. Such material, when worthy, is often run in a furnace, along with litharge, which serves to collect the traces of values. It often requires thinning of the slag by the addition of fluorspar. That creates a very aggressive slag, which readily dissolves the refractory in use. 

*Please lose the "all caps" posting*. Such use is considered shouting, which is not necessary on this forum. It also makes reading a post more difficult. Use caps only when appropriate. 

Harold


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## butcher (Oct 14, 2010)

I agree with harold, the miners back then knew what they were doing and did not miss all that much gold, a while back there was a scam on ebay selling old mining slag telling people it still had a lot of gold in it. 

reworking the slag for what the original miners missed not me, I would be looking for were they were digging before the processed the ore.


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## nickvc (Oct 15, 2010)

butcher said:


> I agree with harold, the miners back then knew what they were doing and did not miss all that much gold, a while back there was a scam on ebay selling old mining slag telling people it still had a lot of gold in it.
> 
> reworking the slag for what the original miners missed not me, I would be looking for were they were digging before the processed the ore.



To put it another way in those days gold was expensive and labour very cheap so they would have extracted virtually all the values possible.


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## Anonymous (Oct 20, 2010)

What we have found in RSA, was waste dumps and sand/slime dams from around 1940 were quite rich in Au and Ag as the pyrite lockup was a formidable wall in Kcn extraction. The old stamp mills had a d90 of 600 micron with very little slime. All the oxedised material on surface was mined but as the fresh bedrock was encounted with its pyrite, recovery dropped to 20%. The same ore milled to 25 micron and intense cyanidation gives 98% recovery, but that which the old-timers did get wasnt lost to the slag readily. Sand dumps from around 1900 yielded up to 100 g/t today once the bottom of the dump was reached. They knew the value was there but could not recover it.


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