Black Sand Samples

alloy_II

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Samples from two different areas, once the weather improves - smelting will begin the top sample certainly shows promise, both by weight and microscope image.

For those interested in smelting the attached file is about the various flux's used and their purpose.

Johns.png

John Sample.jpg

Rod Sample.jpg
 

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alloy_II

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Was thinking of using compressed air to sparge the smelt, this was until I realized I'll need an air dryer.

As an alternative to using nitrates as an oxidizer, I noticed the copper from the mother board had oxidized just from being heated up in an open atmosphere environment.

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alloy_II

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Mold for the copper anodes, just have to trim the excess metal off, then I need to make the crucible tongs.

For the mold release, I brush on a thin layer of waste vegetable oil, turns into carbon instantly when it comes into contact with the molten metal.

Quit for the day, raining.

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alloy_II

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I assume that most of you are aware of the gold bonding wires inside the ram chips, if your just clipping fingers your losing gold.

Copper is an excellent collector of gold.

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alloy_II

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Copper a very good collector for gold and much safer than using lead as the collector metal for smelting.

When cupeled lead gives quicker results in producing a gold button while copper has to be parted leaving the cell slimes to be further refined.

Started work on the furnace tongs, tomorrow Pat has appointments in another town so my day is pretty much shot and the machine shop where I need the torch is closed until Monday.

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alloy_II

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Yesterday picking up the mail at our rural location, Pat had a parcel inside the larger compartment when I deposited the key I accidentally included my truck key key.

Long walk home, got my keys back in this mornings mail drop.

The crucible tongs sitting on a block of homemade soap, still getting a lot of rain. Next sunny day I'll do my smelting and melting.

Also making some copper oxide, another flux ingredient used in certain mix's.

I'll probably give some of the copper oxide to a couple of the local potter ladies. its used to make a glaze of a certain color.

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alloy_II

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Please keep us updated. My area has very fine gold though lots of black sands with visible gold under microscope. I’ve often thought about smelting a few piles of cons. Who knows what could be found.
My crucible was to small to do John's sample in a single smelt so I have two lead buttons. I'll melt those together for the cupellation.

What I do notice is that the lead has become much harder and then tapping a piece of iron against it, makes a much different sound than that of soft lead would.

Soft lead, absorbs the energy from a blow, like a dead blow hammer.

Not expecting any great miracles.

The furnace worked out great, once all the flux has turned to fluid its easy to lift the furnace off and place it aside, tongs worked better than expected, but the crucible in my opinion is junk as it sheds off graphite by the pound during the heat.
 
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alloy_II

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Next on my todo list, during the past week I've collected a number of microwave ovens.

One of the ovens is the inverter type and it works, so the lab now has a microwave.

Each magnetron has two round magnets from those I'm going to make a gizmo to remove the magnetite from placer sand.

Eight to ten magnets will be placed onto a wood shaft machined to the same inside diameter hole that each of the magnets have.

Another spool made from wood placed at the other end, like a treadmill. Only much shorter.

As the sand is sprinkled onto the belt as the magnetite reaches the magnets the magnetic fractions will be carried forward and under the mill frame until it reaches a point where it leaves the magnetic field and drops off of the belt.

A splitter will direct the non magnetic fraction into a separate bin.
 
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alloy_II

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The 100 gram sample, incomplete cupellation with some visible gold.

Both non and magnetic fractions were included in the smelt.

Screenshot from 2022-05-19 10-39-35.png


Screenshot from 2022-05-19 11-11-37.png
 
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alloy_II

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What's needed to clean this up? Different flux? longer smelt more heat?
This is from the 100 gram sample from a well known platinum area, I cupelled it this evening.
'
I suspect there's more platinum than gold as the lead soaked into the Portland what remains of the lead is having difficulty's of soaking into the Portland.

Definitely needs more heat to complete cupellation, Monday I'll use my small crucible then go to the machine shop to use the acetylene torch.

The bigger piece of lead worked very well to collect the precious metals during the smelt, as the lead is soaked into the Portland the and the original piece of lead shrinks in size so does the heat transfer so the platinum freezes up, as you suggested more heat.

I want to see some gold.
 
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alloy_II

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My mistake, I only posted a portion of the lead used during the smelt.

Here's the full size of the lead used, here''s what took place. My cone mold is made from heavy cast iron with thick walls. I did not apply enough heat to the mold before pouring in the molten flux.

The lead did settle out to the bottom of the mold but had some flux encapsulated in the button.

I put the lead button into my small crucible thinking once the lead was melted I could just skim off the flux.

I've melted plenty of wheel weights and its always been easy to skim off the dross, so this was totally unexpected.

As soon as the spatula made contact with the lead the center froze, and it was only that portion of the image I had posted to show the little bit of visible gold.

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alloy_II

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To learn what happens during cupellation when the platinum content is too high.

 
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alloy_II

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Palladium absorbs oxygen when heated, then as it cools it expels this oxygen making it impossible to have a smooth surface.

The crappy button from the 100 gram sample I suspect is palladium because of the pock marks left on the surface made during cool down.

Bottom image borrowed from the internet has a much cleaner surface showing the irregularity's.

pd button.jpg


palladium buttpn.png
 

Ohiogoldfever

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Palladium absorbs oxygen when heated, then as it cools it expels this oxygen making it impossible to have a smooth surface.

The crappy button from the 100 gram sample I suspect is palladium because of the pock marks left on the surface made during cool down.

Bottom image borrowed from the internet has a much cleaner surface showing the irregularity's.

View attachment 2027921

View attachment 2027920
Looks Ike you may be onto something. Thanks for sharing.
 
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alloy_II

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probably the best way to clean up that platinum button would be to remelt with a torch then sprinkle potassium nitrate onto the hot metal to burn away the base metals.

There was a bit of visible gold form the button recovered from the smelt so even after treating the button with a nitrate the button will still be a mixture of platinum and gold.

Selling this type of material one would take a hit on the gold content but in my opinion not enough gold to worry about.

After I clean the button from base metals, I want to know the weight and will send it out for an assay to know which platinum group of metals predominate the button.

One has to be aware of Osmium as this metal an blind you, when its melted.

osmium tetroxide

 

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