Long Tom Sluice

[HardPack]

Has anyone actually seen or even used a “Long Tom Sluice”? I have access to an old claim with an abundance of tailing piles that I suspected were left from the use of a Long Tom (as opposed to a sluice run). If correct there may of been gold discharged and left behind in the piles. Here’s my guess on operation:

It appears the Long Tom was utilized where water supplies were limited. It looks like the pay dirt is deposited in an upper trough to be mixed with water to break up the material then raked across a metal punch plate. The material with a diameter smaller than the punch plate holes dropped into a short (riffled?) sluice box with the larger diameter material tossed aside or pushed off the end of the upper trough. I have not found any reference to the diameter of punch plate holes. 

http://mygoldrushtales.com/wp-content/uploads/2011/04/Miners-in-the-Sierras.jpg

[Valens Legacy]

The early ones had riffles that were dug into the bottom of the deck to catch gold and also some raised riffles.

They make similar units today but are shorter than the old ones, and they also make a mini one that you can take in a back pack. I have seen one a long time ago with my grandfather that someone was still using at the time in North Dakota.The way that I was told on how it worked was that it used less than half of the water others needed to work.

The one I had seen the bottom holes that captured the gold was about 1 1/4 inch in diameter and close to 3/8 in deep. The guy that was using it would dump his material into one end and sweep the real heavy stuff down it or pull out what the water had cleaned. It was a lot of work but he said he could gather more gold than his normal sluices with it.

That is all I know and I may not be 100 percent accurate on how it worked, been a long time.

[HardPack]

10 hours ago, Valens Legacy said:

bottom holes that captured the gold was about 1 1/4 inch in diameter and close to 3/8 in deep

Tempting DIY build. I read the miners could direct stream flow into the upper trough as needed or bucket the water. Cutting a depressed groove in the lower sluice makes sense considering the low water volume. So the shallow 1 1/4” diameter holes were bored into bottom of the upper trough?

[HardPack]

Another view of the Long Tom in operation.

[Dean Stone]

Valens Legacy I think the sluice you talking about is a Drop Sluice. I have a small one that i run my cons. in and it don't miss much. Only use a small amount of water. Once the drops get full of black sand, it will loose some gold, need to keep an eye on it so it fill up.

[Valens Legacy]

56 minutes ago, Dean Stone said:

 I think the sluice you talking about is a Drop Sluice.

The unit that I had seen in the past had 3 different type of ways to capture the gold. 2 different types of riffle plus the holes. On the top portion of the Long Tom there was the slurry box o top and it had some type of slits that went to the bottom sluice. On top they would smash the materials to loosen the gold up, keep raking the mix so that the gold would go to the bottom and to the next sluice. The heavies would be removed from the very end of the top  section and gone through at a latter time. Since the sluice was being used at the time my grandfather and I were there I did not get to see just how the gold went from the top to the bottom.

When I was looking under the top section I could see the shape of the riffles in the bottom section.

I hope this helps,

Caleb

2 hours ago, HardPack said:

Another view of the Long Tom in operation.

That is a better picture of the unit, and that looks like the one I had seen almost 20 years ago.

Above I had remembered a little more about the unit.

[HardPack]

3 hours ago, Valens Legacy said:

I did not get to see just how the gold went from the top to the bottom

The nearest miner in the photo has his square nose shovel turned over, the punch plate is located on this nearest end of the upper trough. The miner is prepared to rake the smaller material back & forward over the end punch plate. Any material too large to drop through the holes in the punch plate is classified as a throw-out. If you look closely you can see the water drops hitting the surface of the lower bottom riffle box. The miners could have dug a water ditch above their diggings, the upper gated wooden flume box is carrying the water as needed to the Long Tom’s upper trough. Their diggings are on the left of the Long Tom with the throw-out piles on the right. Normally the miners would start on the lower portion their placer claim then working the diggings to the higher end. Miners on adjacent claims would often combine their efforts to dig a water ditch parallel to all their claims on the higher ground above the claims. Each claim owner would then cut a weir to draft water from the ditch. The weir and Long Tom location would move up the claim as they worked their diggings. This is the situation I see on the claim I am detecting, the miners were working short sections of elevated cemented bench gravels down to the old bedrock bench that were once the bottom of a stream channel. In this area the water supply was reduced or even dried up during the summer months.

Further down stream on a different claim down in the flats the miners switched to a riffled sluice run using the same type of ditch/weir system. The riffled sluice run would travel the width of one side of the claim on either side of the stream. The larger rocks were throw-out to one side and the smaller material not trapped in the riffles was pushed out the end of the sluice run into the stream. In this “flats” case the riffled sluice runs were a couple of hundred feet long. 

As you can imagine both system were not that efficient at capturing all the gold. You can see in the photo how muddying the water, with the Long Tom any material larger than the diameter of the punch plate holes would be classified as a throw-out. Quartz specimen could find itself a throw-out in both sluicing systems. Unfortunately with the riffled sluice run some gold was deposited back in the stream as opposed to a detectable throw-out pile. 
 

[MSC]

I've made kind of a long tom by putting two sluice boxes end to end. 

[HardPack]

On 2/4/2024 at 5:38 PM, MSC said:

I've made kind of a long tom by putting two sluice boxes end to end

D’arcy Cooper used to fabricate the Boiler Box Dirt Hogg highbanker with a low angle hopper box. Similar to the Long Tom pay dirt with a high clay content is washed prior to dropping through the grizzly bars into the sluice box. The hopper is 36 inches long, the sluice box 48 inches long and tapers from 10 inches out to 12 inches. 

I have lots of clay to deal with plus the current California restrictions on highbanker stream pump out-take and sediment discharge, I’d be interested in a light weight packable version of the Dirt Hogg setup to recirculate with 3/4” or 1“ spray bars, a 12vdc pump(s) and a LiFePO4 battery. And perhaps an optional folding portable 100 watt solar panel with a built in charge controller.