Extruded EPDM 4-TPI Sawtooth Mat Redesign

[dragline]

Geowizard, Johnedoe and any other interested AG Forum users,

Sawtooth Mat update Thursday, 10-Jan-2019: The ship date for my next Ohio EPDM extrusion manufacturing run of the 4-TPI, 8-TPI and 16-TPI Sawtooth mats will be in two weeks, Thursday, 24-Jan-2019 (estimated). I'll update everyone again when I have an estimated delivery date here to my warehouse in Roseburg, Oregon.

For those experienced Alaska Gold Forum users and miners that are familiar with and involved with extreme fine gold recovery technologies, which you both definitely are and assuming you're interested, I'd like to ship you some free samples of my latest run of Sawtooth mats for your evaluation and testing. PM me your requirements and shipping info.

Jim, thank you for keeping Alaska Gold Forum going for 15 years now, providing a place where miners can freely exchange ideas and help one another in the expansion of their knowledge and potential for the pursuit of this wonderful and beautifully shiny metal.

dragline

[Geowizard]

dragline,

Thanks for the reply.

Early mining was done by conventional Dozer, Hydraulic Monitor and Slice with Dragline for stacking tailings from 1930 through about 1960. The larger portion of the GOLD passes 20 mesh. I don't screen the GOLD further during cleanup because the TIME needed for each smaller mesh increases the time for cleanup exponentially.

Yes, I have a binocular microscope and a micron ruler. The smallest perceptible GOLD runs 10 to 50 microns. I have never "tried" to recover this GOLD but... it shows up in the bottle at the end of the Cleanup anyway. I run blue Bowls at the 50 micron level for finishing. I hand pan the Blue Bowl super cons., scope it and send it to the refiner.

Disseminated GOLD source;

At 20 mesh, the gold is flat and in it's natural form. The 20 mesh GOLD comes from disseminated GOLD sources where the GOLD was formed in micro fractures in sandstone/siltstone bedrock. When the GOLD gets smaller than 100 mesh is rounded from having been formed in pore spaces in the sandstone/siltstone bedrock.

Settling theory;

Settling theory as applies to ribbed mat and Hungarian riffles does NOT apply in my case.

Here's why;

The industry standard in the interior of Alaska is Expanded over Astro turf. The old school standard was Cocoa mat. There is NO theory that can be applied to the infinite number of possible random paths of circulation around expanded over Astro turf. Suffice it to say, the combination satisfies the natural laws of physics to allow settling of micron GOLD. Note also that the Alaskan Tundra has abundant micro-fiber moss (aka Alaskan mner's moss) that becomes interwoven in the expanded and Astro turf to create micro-vortices and micro-eddies! It's so efficient that ALL of the GOLD is found in the TOP 4 feet of the sluice. There isn't enough GOLD in the last 4 feet to buy a pizza!

The ROSS BOX;

Having studied the ROSS BOX, I am brain storming a scaled down version. The ROSS BOX runs everything out the end of the box from 12 inch boulders - on down. We're talking several levels of punch plate, over-under recovery down to low and slow for micron GOLD!

- Geowizard

[Jim_Alaska]

Jim, thank you for keeping Alaska Gold Forum going for 15 years now, providing a place where miners can freely exchange ideas and help one another in the expansion of their knowledge and potential for the pursuit of this wonderful and beautifully shiny metal.
dragline

You and everyone else are very welcome Dragline. These forums have been a work of love since the very beginning, when I lived in Alaska. My original intent was to have a place where Alaska miners could fellowship and exchange ideas. It has far exceeded that simple goal, the quality and volume of expertise that resides on our forums far surpasses any other and is way beyond my hopes and dreams.

I also wanted a place where miners from all other locations could come and be educated by real experts in the field of mining and gold recovery means and methods, whether they were professionals or newbies.

My only regret is that I was not able to migrate all the old info from the old forums to the new. But they are still there for anyone that wants or needs to save any old information. I have locked them so they are not interactive, but the information can be copied and pasted by anyone.

[dragline]

Geowizard,

Right. I've seen photos and a few videos of the Ross Box in action on tailing piles and it is an amazing thing to see. It definitely seems like one of the highest production ways to go if you're not dealing with major cobbles and boulders. But since it sounds like you've got a lot of boulders in your tailing piles, I can see how your mention of including multiple successive punch-plate screenings so as to process all fractions of the material simultaneously would be profit optimal. My suggestion is that it might further your goal of profit optimal recovery to use different sluice riffles, GPH and slope for each, slowing the slurry velocity and decreasing the slope as the screen sizes are reduced.

Ross Box

dragline

[Johnedoe]

Check out this beach mining equipment... Granted they are selling jewelry but the mining equipment is something.......

https://www.ashhilton.com/pages/pure-ne ... beach-gold

[dragline]

Johnedoe,

That's a very interesting article you linked to with your last post. I've seen that New Zealand beach mining operation written up a few times over the years and am always amazed at how far these miners have pushed extreme fine gold recovery technologies.

Notice the second photo in the article here:
https://cdn.shopify.com/s/files/1/0438/ ... _large.JPG

There are a few key points about the specific technologies employed with this operation that I'd like to call to this forum's attention. If a picture can sometimes be worth a thousand words the photos in this article seem to speak volumes. After counting pixels in this photo and applying a little trigonometry, and after assuming the man in the overalls is about 6 feet in height, we can come to the following assumptions about this operation:

1. In this second photo we can see there are a total of 4 levels each with 2 four foot wide sluices per level. That makes 8 four foot wide sluices running in parallel for a total effective sluice width of 32 feet. Wow! Can you imaging? ...a 32 foot wide sluice!?!?

2. Now take a look at the slurry pit in this same photo. While it doesn't appear that any of the people in this New Zealand beach mining operation are our forum member Trev, who is also a beach miner from New Zealand, perhaps we can draw a few more assumptions based upon Trev's accounts of his NZ beach mining operation. We can therefore also assume that you are looking at a beach sand slurry pit that was created by pumping water down into and liquefying the beach sand. A beach miners then use a dredge to suck up that sand slurry and pump it over the sluice.

Now take a look at the third photo in the article here:
https://cdn.shopify.com/s/files/1/0438/ ... _large.JPG

3. In this photo we see a side view of the operation and after counting and calculating pixels for scale we can determine that the length of each sluice is approximately 2 meters (about 6-1/2 feet) and the sluice slope angle is 13°. Interesting?

4. But wait! You may choose to disagree, but what I see is an additional two levels of sluices directed opposite the slurry pit. I can also see the two 4 inch (blue) discharge pipes for these two additional sluices levels in the previous photo (#2). That makes for an additional 4 four foot wide sluices! Can it be a total of 12 four foot wide sluices or an effective sluice width of 48 feet? At a length of 6.5 feet that makes an unbelievable sluice capture area of 312 square feet!

5. Did you also notice the staked polyethylene sheeting that separates the slurry pit from the trailer and foundations of the sluice, pump and tractor? Without this barrier the slurry pit would eventually expand to engulf and consume the entire operation! What a sophisticated operation this is!

Question: Has anyone here on Alaska Gold Forum ever seen or heard of a sluice that was either 48 feet wide or a sluice with a total capture area of 312 square feet? It seems to me there might be a Guinness world record here. Let me know if you know of a larger sluice than this.

Johnedoe, thanks for calling our attention to this amazing beach mining operation. When it comes to extreme fine gold recover it definitely seems as though we can learn a thing or two from this miner's technologies.

dragline

[Johnedoe]

Hey Dragline.

I know a beach or 20 that I would love to put some similar equipment on....

It was great to see you today and thank's again for lunch.
Looking forward to getting together again soon and moving some sand.

[Steven G]

where can one buy the mat when Available?

[Joe S (AK)]

I have used Dragline's original 4 TPI matting on beach sand and found it to be a real Gold Grabber. In fact, I spent a few hours with Dragline and Johnedoe *and* the saw tooth worked exceptionally well there on the beach in Oregon.

I wonder if the 8 and the 16 Tooth next generation styles would do better - all three sizes in combination down the box (to provide 3 or more different dynamics for drop zones). I have found that one, monotonous, drop style down the entire sluice will, sometimes, pass and pass and pass and pass individual, difficult sized/shaped Gold pieces and even allow a very small % to skip completely through the drop field. I have also found that breaking up that repetitive pattern with other sized drops, and the flow dynamics that those interactions produce, create 95+% recoveries.

So, a hearty "Good Job" to you Dragline - let us know how the new 8 and 16 TPI sizing works out for you on that very small Gold - especially in combinations with the original 4 TPI sizing. Those different size combinations way well do really well for small, classified, beach sand or any other generated concentrates.

Joe

[dragline]

Joe S (AK),

Thank you for your kind words. You make a good point about the limitations of a completely uniform recovery system for extreme fine gold sluices. No single system seems to work perfectly. But because some systems are optimized for differing gold particle characteristics a mix of systems will usually have a positive impact on overall recovery.

Sawtooth Update 12-Feb-2019: I've experienced a delay with my latest Sawtooth extrusion manufacturing effort. Last Thursday I received samples runs for all three extrusions, i.e. the 4-TPI, 8-TPI and 16-TPI mats. The 4-TPI extrusion sample, as expected, was perfect since that extrusion die was previously manufactured in 2012 and no changes have been made to that die since. However, I was not satisfied with the 8-TPI and 16-TPI samples and after discussing the problems I saw with the EPDM extrusion engineers I decided to redesign both tooling dies so as to hopefully achieve more optimal results for both mats. I asked my EPDM extrusion manufacturer to proceed with the 4-TPI production run separately from the 8-TPI and 16-TPI extrusions and hopefully I'll have an update soon regarding my ETA for more 4-TPI Sawtooth mat. Owing to the die fabrication and additional sample runs needed I anticipate that the 8-TPI and 16-TPI mats will likely not be manufactured and available until mid-April at the soonest. Again, I'll provide updates on those mats as warranted.

dragline