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What are some or all of the reasons for mapping or surveying the Goodyear Gold Mine?
Like the videos and thanks for posting. Thank you.
 

What are some or all of the reasons for mapping or surveying the Goodyear Gold Mine?
Like the videos and thanks for posting. Thank you.

There's a slew of reasons for it, but I'll start with what Kyle had shot as far as video for us.

Originally all I knew is that we had two forks, one crosscut with possibly more, a lot of drifts and stopes, the adit dipped on the Right Fork, some timbering, and a pretty good sized stope at the end.

What do we need to know then?

Are there multiple crosscuts because if there are a lot of them there may be a lot of ore removed.

Do the forks cross under each other or are they joined at a terminus with a crosscut? If they cross over/under what is the diameter of the crown pillar? Does the timbering support the crown pillar or is it not related? If there is a terminal crosscut, can we use the shape of the mine to form a flow pattern for ventilation?

How much ore/gangue has been removed? With basic length we can tell how extensive the workings. How much air ducting will we need? Rail? Electrical lines? Air lines?

Is there evidence of core drilling? If so, where? Are those drill holes on a pattern or seemingly random?

For each drift, is there still ore visible or stoped out? How many feet? How big are the stopes? Is there backfill (we knew there was some) that may need to be removed for safety?

what directions do the forks and drifts go? How far can we extend those before running off the boundary of our claims? Is there any danger of running off the boundary?

Does either fork have a danger of opening up to the surface due to topography?

What's the general slope of the forks, drifts, or crosscuts? How much of a pain in the bass is it going to be to move ore in cars in the mine?

How many areas are sloughing? Are they related? Do the geology changes seem to be correlated to it? How many areas off the roof have caved?

How large is the working face?

Where are the timbers if they're not related to the crosscuts or forks crossing under each other? What condition is it in?

Does each fork follow the same vein or is it a series of workings not related? If one dips, is it chasing multiple levels of veins or following a dip?

Is there any airflow? If so, where's the source? Which fork? Which Drift?

If the mine makes water, where's it start/stop and is there any flooded winzes or stopes?

That's a good starter for what I was looking for.
 

There's a slew of reasons for it, but I'll start with what Kyle had shot as far as video for us.

Originally all I knew is that we had two forks, one crosscut with possibly more, a lot of drifts and stopes, the adit dipped on the Right Fork, some timbering, and a pretty good sized stope at the end.

What do we need to know then?

Are there multiple crosscuts because if there are a lot of them there may be a lot of ore removed.

Do the forks cross under each other or are they joined at a terminus with a crosscut? If they cross over/under what is the diameter of the crown pillar? Does the timbering support the crown pillar or is it not related? If there is a terminal crosscut, can we use the shape of the mine to form a flow pattern for ventilation?

How much ore/gangue has been removed? With basic length we can tell how extensive the workings. How much air ducting will we need? Rail? Electrical lines? Air lines?

Is there evidence of core drilling? If so, where? Are those drill holes on a pattern or seemingly random?

For each drift, is there still ore visible or stoped out? How many feet? How big are the stopes? Is there backfill (we knew there was some) that may need to be removed for safety?

what directions do the forks and drifts go? How far can we extend those before running off the boundary of our claims? Is there any danger of running off the boundary?

Does either fork have a danger of opening up to the surface due to topography?

What's the general slope of the forks, drifts, or crosscuts? How much of a pain in the bass is it going to be to move ore in cars in the mine?

How many areas are sloughing? Are they related? Do the geology changes seem to be correlated to it? How many areas off the roof have caved?

How large is the working face?

Where are the timbers if they're not related to the crosscuts or forks crossing under each other? What condition is it in?

Does each fork follow the same vein or is it a series of workings not related? If one dips, is it chasing multiple levels of veins or following a dip?

Is there any airflow? If so, where's the source? Which fork? Which Drift?

If the mine makes water, where's it start/stop and is there any flooded winzes or stopes?

That's a good starter for what I was looking for.
Thanks for sharing as many people will not think about some of these questions. Plus some of this is a learning curve that is for sure before spending time, energy and money for some of the mining operations. Some of this can be useful in proving the steps to take for "Economic values" extractions. Others may have some extra factors to look at in the mining operations.
Many people will not be able to carry out some mining operations without help.
 

There are many more areas in this bad boy that need exploring that raises more questions. Such as did they drive the left fork first searching for a lens of ore, or on the right fork secondly then found one or vice versa? Its also good to have an idea if the tunneling goes in the direction of an outcropping on the surface.
 

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Do you guys have a favorite assay company?
Many of the western states used to have 'Mining and Metallurgy schools or universities'. May not hurt to ask at these as there may be people left to talk to. May not hurt to read a copy of Manual of Assaying by Alfred Stanley Miller, Professor of Mining and Metallurgy, University of Idaho. California should have a like book. The time frame is around the turn of the century (!900's).
 

Crushing say a ton or more of ore rock and processing after the the "Free milling values" are released from the ore rock will also give a better idea of the real values present per 'Block of ore rock'. The Fire assay will pull all 'Values out' "Free milling or not" is the difference in the sample tests.
The Fire assay is excepted around the world when it comes to selling the "Economic values".
 

Crushing say a ton or more of ore rock and processing after the the "Free milling values" are released from the ore rock will also give a better idea of the real values present per 'Block of ore rock'. The Fire assay will pull all 'Values out' "Free milling or not" is the difference in the sample tests.
The Fire assay is excepted around the world when it comes to selling the "Economic values".

Your assay can tell you if you’re dealing with free milling or high sulphides
 

Crushing say a ton or more of ore rock and processing after the the "Free milling values" are released from the ore rock will also give a better idea of the real values present per 'Block of ore rock'. The Fire assay will pull all 'Values out' "Free milling or not" is the difference in the sample tests.
The Fire assay is excepted around the world when it comes to selling the "Economic values".

"Free Milling" refers to what can be picked up by cyanidation, not what you can recover with a gravity separation process. Quite often you can have "high sulfides" and still have "free mill gold". The sulfides just eat up the cyanide in the process.
 

Free mill only means the gold is not refractory ore aka needs roasting or other pre treatment. Free mill can be crushed and panned IF the particles are large enough. Microscopic still needs cyanide or something similar for recovery. Its kind of a misleading term. Even if your particle size is large enough to just mill and gravity separate its a good idea to see if your just throwing away micron gold which could be recovered by leaching.

But its a good point..it can for sure be a mix of both refractory and free milling. In some districts they just discarded the sulphides and just went for what they could get with milling then amalgamation..
 

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Still learning about this. Thank you both Mad Machinist and StreamlineGold for the information.
 

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If the Ore contains small percentage of sulphur desulphurization can be by means of iron nails and is a standard means with a fire assay page 65b assay of so-called refractory ores (manual of assaying Miller).
Amalgamation and chlorination tests are usually intended to give an approximate indication of the percentage of gold and silver that can be extracted by these methods on a working scale page 82. The mesh size of ore sample for amalgamation is 80-mesh. The mesh size of ore sample for fire assay is 40-mesh. The Chlorination test calls for a "Roast" of sample before the test.
 

"Scorification Assay"

A "Scorification Assay" is often used when there is rich gold and silver ore. The problem with this test is that the "Scorification assay gives higher (uncorrected) results for silver" page 43 Miller. This of course is a type of fire assay.
 

Just posted the above to give everyone a idea of what a assayer may be dealing with with different types of rocks. Most people will not be dealing with the volatilization of bad things like sulphur, arsenic, mercury, lead, etc,.
 

Most ore is going to have a least some pyrite in it which can be mixed with arseno..I I have into a lot of ore with a garden variety of chalcopyrite, arsenopyrite, galena mixed with free milling gold. The levels of which made the difference whether it should be considered a complex ore or not.

Galena (lead sulphide) in particular can run into the hundreds of oz per ton of gold. Its tough to assay those sulfides eat..
 

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