Looking for guidance

[Mineral Madness]

I've been trying to teach myself how to extract gold from crushed Rock using hydrochloric acid and bleach and I've gotten less than favourable results. I know the gold is there I'm just not sure bring all the steps necessary to extract the gold from the material because I have failed to precipitate anything back from the liquid. I have failed a dozen times so far and I'm starting to get discouraged, I could really use some advice from experienced and knowledgeable individuals who have done this process before using crushed and powderized rock.

 

[FrugalRefiner]

How do you "know the gold is there"? Have you had it assayed?

Mixing acid with rocks can be a deadly combination. I would never do it without an assay to tell me about harmful elements, like arsenic, that might be in the rocks.

Dave

 

[Lino1406]

Crushed - should be wholly to 100 mesh. Roasted - to 700C. Then try extraction again, all in ventilated area

 

[Mineral Madness]

How do you "know the gold is there"? Have you had it assayed?

Mixing acid with rocks can be a deadly combination. I would never do it without an assay to tell me about harmful elements, like arsenic, that might be in the rocks.

Dave

Admittedly I am relatively new at prospecting so humbly I am no expert in any of this but I do a lot of reading and research when something catches my interest so I do have a wide variety of basic knowledge that I've acquired myself over the past 6 months. I found gold by panning some of the crushed rocks that's how I know it's here. In Ohio 85 to 90% of the gold you find in local Creeks is trapped in conglomerate rock and my property is littered with conglomerate rocks of all sizes.

 

[Mineral Madness]

Crushed - should be wholly to 100 mesh. Roasted - to 700C. Then try extraction again, all in ventilated area

Since I only have six months of experience in prospecting and chemistry I'm interested to know exactly what roasting the material to 700°C does if you would be so kind as to explain.

 

[Lino1406]

Roasting oxidizes sulfides, arsenides tellurides (if present) which lock the gold, to oxides

 

[Mineral Madness]

Roasting oxidizes sulfides, arsenides tellurides (if present) which lock the gold, to oxides

Thank you Lino. That kind of information is exactly why I joined. Are there any other possible obstacles I should be prepared to run into as I move forward?

 

[orvi]

Processing complex sulfidic ore for gold by leaching it with acids is not a very good option. Generally, pouring acids on rocks does not work well.
You say that you found pannable gold in the rock. So that is a good start. Stick to that I suggest. If you want to invest more into assesment of values, make representative sample of your ore and let some trusted lab perform a fire assay of it. That way, you will know for sure what is in there and if it is worth chasing.
Truth is, if you find a sulfidic/microscopic gold deposit, which require fine milling, producing concentrates and then smelting - or worse, if cons cannot be made, cyanide leaching... On small scale, this require very, very rich ore to be profitable.
Also, never roast/smelt any rock for which you do not know the precise composition. In sulfidic ores mainly (but not generally), arsenic, selenium, tellurides, mercury and cadmium could be present in sometimes very scary ammounts. If you intend to roast that type of ore, you volatilize all of this junk to the air and poison you and your property with heavy metals and harmful stuff. That is certainly nothing you would like to do. You cannot smell them specifically, resprator is only of little help, if any. Be aware of this fact.

 

[DaddyD]

I have been a prospector and miner since 1984 I have never used acid or mercury just panning and slucing

 

[BlackLabel]

In Ohio 85 to 90% of the gold you find in local Creeks is trapped in conglomerate rock and my property is littered with conglomerate rocks of all sizes.

But beware: More than 99% of these conglomerates does not contain any gold.
;-)