Clay Assay

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I was finally was able to get the blue clay assayed. Wondering if you guys can look them over and let me know if you think there's anything interesting in these results and if the clay is worth anything for refining? The deposit is very easy for me to get to with my excavators as I'm digging the gravels off above and below it anyways to process for the placer gold.
The clay comes off in nice compact chunks from 6" to 3 feet thick in areas. Lays down like a sheet. Some local geologists figure it may have been the bottom of the old glacial lake beds that formed when the glaciers moving through formed ice dams causing water ways to build up in those areas. There is almost no rock in it at all. Very fine grained. I have been stock piling it so far separate from the gravels just in case there's something I can do with it.

Also curious if you guys might be able to tell what elements in this assay might be giving it the blue color it has.
 

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Your analyses show nothing of value in the metals.

There is a strong possibility of a market in the artisan field as potting clay or as a glaze precursor.

Find some local hobbyist and get them to do a few tests for you.

If the colour is from organics then you will most likely lose it during the firing stage.

It is always worthwhile to have a sulfide containing bedrock analysed for precious metals, the easiest method is to crush some of the rock and pan off a sulfide concentrate for analysis. This way the lab can flux just for sulfides and minimise fluxing problems you get with an unknown ore sample.

Deano
 
The blue might be coming from the minerals associated with the Titanium. This open pit Titanium mine has a very blue color in the deposit.
 

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Sounds like a typical glacial clay to me. Aluminium silicates with a few trace minerals.

The color of the clay could be anything but blue is quite common among glacial clay... at least where I live. There are one mineral that could be responsible for the color and it's a phosphate, vivianite. There is some organic material in the clay (judging from the carbon content) and vivianite can form from organic residues in quite a short time. There are some phosphates in there according to the assay so that is my guess.

https://en.wikipedia.org/wiki/Vivianite

Göran
 
g_axelsson said:
Sounds like a typical glacial clay to me. Aluminium silicates with a few trace minerals.

The color of the clay could be anything but blue is quite common among glacial clay... at least where I live. There are one mineral that could be responsible for the color and it's a phosphate, vivianite. There is some organic material in the clay (judging from the carbon content) and vivianite can form from organic residues in quite a short time. There are some phosphates in there according to the assay so that is my guess.

https://en.wikipedia.org/wiki/Vivianite

Göran
Yes I think it's a glacial clay for sure. Interesting about the Vivianite. I'm going to talk to the lab guy that did the assay and ask him if he can identify the minerals responsible for the elements in the clay. But I think that may not be possible without further tests. From my readings there's two main minerals that the Titanium could be. They are Ilmenite and Rutile. A lot of the Titanium deposits around the world are sedimentary sand/clay deposits. And most of them appear to be in the same concentrations as what's in this clay.
Would you happen to have a guess as to what minerals the aluminum may be? Do you think it would be just in the Aluminum Silicate form? If that is the case do you think it would gravity separate from the Iron and Titanium metals?

I watched a good video on Titanium processing from sands and looks like they first gravity separate the metals from the silica etc then use electrostatic separator to separate the magnetic iron from the non magnetic metals. Then they use the Kroll process to create a Titanium sponge them purify it further from that.
Looks like what a lot of mines do though is just half the process of gravity separation and sell the concentrate ore to overseas countries.
I'm just looking into this a bit because for me placer mining the gold I have to process all the gravels above and below the clay layer anyway so I may as well stock pile it and then try to sell it if I can.
There are four companies in BC Canada not too far from where I'm mining that can process clay in large amounts but not too sure about getting full refining of the Kroll process done here. I will find that out on Tuesday when they open back up. If ACME can do it then that would be a real easy delivery/sell for me cause they are close and reputable to deal with. They have a sister ore refining company here. There is at least 100's of thousands of tons of the blue clay on my claim but probably much more like millions of tons cause I have hit it in my testing everywhere I have dug so far which is hectares of testing along the valley bottom near the creek.
If a company wants the clay for the metals in it then I can either truck it out in it's natural form or if it would save me a lot of money in transport costs and more money in selling a concentrate then I could semi process it right on my claim site then transport it. But would be a lot easier to just sell it in it's natural form.
Even if it's just a bit of extra income to the mine then it helps pay for stepping up to production phase of the gold mining. Just my thoughts about it so far anyways.
 
I'm suspecting I have seen the same youtube videos you have. I think clay would be a lot harder to process to get the titanium out. The grains are too small for normal processing, just as catching very fine gold in a wash plant. The finer the material the longer it will take to separate it. This clay was deposited in a slow or stationary water over a long time, the individual grains stays suspended in water for hours or days before settling.

You can always check with the companies that process clay. They should know best and they also know about your local geology.

Just forget about the aluminium. When minerals as feldspar and other aluminium silicates weathers it breaks down into clay-minerals which still is aluminium silicates but enriched in aluminium. The next step is when clay weathers, then the silicate is washed away (millions of years) and remaining is aluminium oxide and hydroxide. That is what bauxite comes from, the most common aluminium ore.

If the phosphorus is in the form of vivianite or some other mineral is just an academic question. It would be fun to know but hardly something worth spending a couple of hundred dollars on. With a SEM (scanning electron microscope) equipped with an EDS (basically an XRF but for a SEM) you could find it out quite easily, but that's some expensive equipment... I should know as I got one. :mrgreen:
... but I haven't had the time to put it in order yet, I suspect I have some work to do on it before I can run any samples. I would be very surprised if I don't have to do some repair on the system before getting it up and running.

Göran
 
g_axelsson said:
I'm suspecting I have seen the same youtube videos you have. I think clay would be a lot harder to process to get the titanium out. The grains are too small for normal processing, just as catching very fine gold in a wash plant. The finer the material the longer it will take to separate it. This clay was deposited in a slow or stationary water over a long time, the individual grains stays suspended in water for hours or days before settling.

You can always check with the companies that process clay. They should know best and they also know about your local geology.

Just forget about the aluminium. When minerals as feldspar and other aluminium silicates weathers it breaks down into clay-minerals which still is aluminium silicates but enriched in aluminium. The next step is when clay weathers, then the silicate is washed away (millions of years) and remaining is aluminium oxide and hydroxide. That is what bauxite comes from, the most common aluminium ore.

If the phosphorus is in the form of vivianite or some other mineral is just an academic question. It would be fun to know but hardly something worth spending a couple of hundred dollars on. With a SEM (scanning electron microscope) equipped with an EDS (basically an XRF but for a SEM) you could find it out quite easily, but that's some expensive equipment... I should know as I got one. :mrgreen:
... but I haven't had the time to put it in order yet, I suspect I have some work to do on it before I can run any samples. I would be very surprised if I don't have to do some repair on the system before getting it up and running.

Göran

This is the Youtube video I was referring to: https://www.youtube.com/watch?v=41yjeguApo4

I have been thinking the same way that the particle sizes may be too small for gravity separation of the Titanium from the clay. So I processed 5 lbs of it the other day to extract the solids and separated them into different mesh sizes. The smallest screen I have right now is 230 mesh so I've got the clay/water slurry that is remaining in my garage in a garbage can to let the solids settle down for a week or so then I plan on screening that down further with a 400 mesh if I can find one to buy. This way I can see what mesh size the Titanium minerals are showing in more than others. I will phone both the clay processors and the Titanium processors on Tuesday to see what mesh sizes they can process. I have read though that they process a lot of sedimentary deposits of it from sands to clays. There's one in Africa I read about that said it was a sand and clay deposit of an old river channel.

So when you say forget about the aluminum, why is that? Is it too hard to refine aluminum from aluminum silicates? And it's easier to refine aluminum oxide?
Could it be that there is aluminum oxides in the clay? Is there a special assay that can tell me that without doing a full minerology report like a Qemscan? Those are pricey as I have done them on hard rock ore.

The organics in the clay are very small plant fibers like hair roots. They are very light weight and separate easily from the clay.

Glacial clay is very popular with clay cosmetics but I think the 10ppm of lead reading may not allow me to use it for that. Supposed to get a call back next week from one of the big clay cosmetic manufacturers next week about that. I've tried finding the info online about the heavy metal allowances for cosmetic clay but I can't find anything substantial about it written by the government. The clay company should be able to give me that info though.

There is a lab close to me where I live that wants to look at the material I have from both my sluice concentrates and the clay concentrates and they have an SEM. The owner has been very helpful with questions I've had in the past and invited me by next week to talk to them about this stuff. He did a free test on some Schist ore I had cause we had a lot in common about prospecting etc too and was curious what mineral was in the ore that was conductive. Turned out it was pyrrhotite crystals. I was getting detector sounds in the ore from my Falcon MD20 wand. Anyways they are super nice folks and it's a small lab so gonna go by there next week with some samples.
Very cool you have an SEM. I imagine your gonna have a lot of fun with that!
 

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It seems you are well connected. It's a good thing to be able to float ideas to different people. You have a lot of good connections there and I hope you'll find usage for your clay. But as a metal ore I don't think you'll find any economy in it

Aluminium is the third most common element on the Earth. This is just the mean values according to Wikipedia.
Oxygen 46%, silicon 28%, aluminum 8.3%, iron 5.6%, calcium 4.2%, sodium 2.5%, magnesium 2.4%, potassium 2.0%, and titanium 0.61%. Other elements occur at less than 0.15%.

Your clay contains 28% silicon and 8.9% aluminium, just above the mean value of the crust. Any random rock you pick up have about 50% chance to have more aluminium than your clay.
https://en.wikipedia.org/wiki/Abundance_of_the_chemical_elements
Comparing the numbers also shows your clay to contain less titanium than a random rock in average. So I have a hard time to see any values in titanium and aluminium.

Yes, a SEM is a fun toy. I bought my at scrap price a couple of years ago and have moved it three times as I've been forced out of my rented space. I finally got fed up moving all my stuff and bought a house outside of town. So next time I move it's my own choice. When I bought it I already had a TEM that I got as scrap (1.8 tons of technology), but I decided to sell it as there were no space in the house.

I have finally started to get some order in the chaos and the first priority is to build my lab with dual fume hoods. After that I might set up the SEM, but I have more projects too... and work now and then to pay for my playtime. :mrgreen:

Göran
 
I spent some days last week and today talking to titanium refiners and the big one in the USA told me they have migrated away from processing raw sands for the titanium and moved to refining concentrated titanium minerals now. So they are getting shipments of concentrates from 50 to 95% Rutile and Ilmenite mostly.
There are processors working with sedimentary deposits as low as .5 % and up but they are in other countries unfortunately.
So I called around to clay processing plants for uses in other industries and two of them, one in Canada and one in the USA want samples. The one closer to me wants a sample asap as they think they can put it into production right away. They both looked at the assays. They are gonna fire it to see if it is suitable for their needs. One of them said they would take 40 tons if it meets their criteria as soon as I can get it to them. Which would be next spring now anyways but still pretty good news if it works out. They even pay for the trucking costs.
Sending them samples in the mail tomorrow.
 
Sounds good. Maybe not the titanium mine you were looking for, but at least you found some use for your clay. What are they using it for? Pottery?

Göran
 
g_axelsson said:
Sounds good. Maybe not the titanium mine you were looking for, but at least you found some use for your clay. What are they using it for? Pottery?

Göran

Pottery was one of the uses he said it may meet the criteria for but he also mentioned some other industrial uses that he said he would email me more info on. I asked him if the heavy metal content was of any concern like the 10ppm lead and 5.6 ppm arsenic and he said no, not for the uses it should be good for. So I am wondering how they will fire it safely with the arsenic in mind.?

I've actually just started looking into that today because I remembered a thread on this forum about arsenic in ore's and to be cautious about it when handling, roasting etc.
So maybe someone can help me here about this? If the aresenic in the clay is at 5.6 ppm is that dangerous to handle it by bare hands? Is it dangerous to boil off water from the clay sands after I mix it with water to classify the sands in it? Or is it only dangerous if roasted at high temperatures? So far I have done this outside but just started worrying about that today as I have a larger amount to boil off the water from today and remembered that arsenic thread.
 
Ceramic tile, toilets, even catalytic converters.

The fine grained clays like those found in sedimentary streambeds all have similar working properties that make it nice to form.

They are also stable for firing, so they don’t shrink too much.

Things like bricks they prefer the red clays of the rust belt. Lots of shrinkage in firing.


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snoman701 said:
Ceramic tile, toilets, even catalytic converters.

The fine grained clays like those found in sedimentary streambeds all have similar working properties that make it nice to form.

They are also stable for firing, so they don’t shrink too much.

Things like bricks they prefer the red clays of the rust belt. Lots of shrinkage in firing.


Sent from my iPhone using Tapatalk

Thanks for that info. Yes I think those are the industries he was referring to other than pottery. He was using a lot of technical terms of different clay properties and I was getting a bit confused in it all lol. Seemed like he was having a good time trying to explain it all to me and I was enjoying listening to it too. Looking forward to learning more about it all.
This glacial clay is very fine grain like you say. I just sieved another batch from my sample with 37 micron/400 mesh and about 95% of it went through that size no problem. I don't have any smaller sieves but I think it's save to say there's probably a lot of 800 mesh and smaller particles in it. Even the 400 mesh it feels like a thick paint consistency. Super smooth feeling. I'm going to do the math tonight on the different %'s of the mesh sizes in the sample I sieved. But I think out of the 57 ounce sample it's around 95% or more smaller than 400 mesh/37 micron. When I boiled off all the moisture from the -400 particles it wanted to all bind together and went to a cement like hardness very quickly. So I think that's probably a good thing cause it wants to bind together even under a low slow heat. I really have no idea but my instinct says that under high heat it will bind together very solid which should be good for any of those industries. The clay is 5% iron so the one fellow was saying he thinks it may fire to an orange color but time will tell. I guess those colors don't come out until it's fired much hotter cause under the low heat I put it on to remove all the moisture kept it still a grey/green/blueish color but more on the grey side. I think they will probably fire it next week some time. Very interesting stuff.
 
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