Selecting a sluice box:

1.  When choosing a sluice box be aware that there are several types on the market produced by several companies.  Some prospectors swear by Keene, others by Pro-Line.  Some will tell you another brand.  Many sluice boxes have gimmicks, bells and whistles to help them sell. 

The components of a sluice box are quite simple.  They are generally constructed of a heavy gauge aluminum. With a flared mouth, a trough approximately 12" wide, down the trough is a set of removable riffles. They range from two feet to five feet in length.  Some may be wider than others, they all work off of the same principle.  Often the bottom of the trough is covered by some type of removable, rippled carpet to catch the fine gold as well as black sands.

Other designs carry a ribbed rubber mat at the entrance to the trough to catch the fine gold before it gets caught behind a riffle, it looks nice, but is not necessary.  You can add one yourself later if you wish.

There are some "mini sluice boxes" constructed of plastic, I have never used one personally.  They seem to be a neat idea for being able to place it in a bucket to cut down on being so cumbersome.  As with their metal cousins.  However, they will not hold near the concentrates as their cousins either.  You could be losing valuable concentrates.  If you are looking in an area where nuggets are common.  And this is what you are searching for, this may be what you want...

Most sluices run somewhere around $75.00 to $150.00 depending on the company and features.  Starting out, a used sluice "box" would be a worth while investment.  They can often be located on the net as well as "gold outings" by local clubs.  I have even had some home made ones given to me.  That work quite well.

2.  How does a sluice box work??

A.  A sluice box's mechanics are very simple.  When you place your "material" on the front of the sluice box.  The water flow carries the material down the trough where it is separated by weight. The heavier items remain on the sluice box.  The lighter ones are carried off the back.  This is a little simplistic.  But this how it works.

When you place the material on the front of the sluice box, you will notice that the material is taken down the sluice box from the top and sides.  The longer it remains, the smaller the pile.  as it is carried the heavier items fall to the bottom.  The lighter items tend to rise.  Gold being 19 times as heavy as water falls rather quickly and is rolled along the bottom.  When it crosses a riffle it will fall over it.  The riffle works against the flow of the water.  It creates a back current.  The heavier items are swept forward under the riffle against the current of the water flowing through the box.  When you witness it first hand it is pretty neat to watch. The water flows one way, the black sand and heavier stones seem to crawl back up the trough against it until it rests at the back of a riffle.

The gold and the heavy black sands will separate out last, the lighter material will go rather quickly.  As the pile of mud and material begins to go through the box you will notice that the black sands cling to the bottom of the box.  This is because they are heavy, the rushing water can't carry them as fast.  If you have a lip or a joint in the mouth of your box where the flare is joined you will notice that  a broad band of black sand will gather.  The lip acts as a riffle it's self.   You will often find the gold and black sands in the first foot or so of the trough.  The lighter black sands will separate out by weight.  I have prospected in some places where there was so much black sand that it flowed off of the back of the sluice box no matter how I tried to keep it on.  Experience has taught me that most of it did not contain anything valuable to begin with.  If it had it would have been heavy enough to stay on it's own.  This is not a problem unless you "choke" the sluice box with too much material. So that it does not have time to separate the material before being "blown" off the back of the sluice box, back into the stream from whence it came. 

The box you use will be determined by your personal preferences.  The shape of the flair can be broad, wing shaped, any number of ways.

I recommend getting one that has a rippled carpet, or one that is rough.  This will act like a trap itself.  If the carpet is smooth the material will simply wash across it like the bare aluminum it rests on.

If you compare the riffles of a sluice box to those of a dredge, you will see there is quite a difference in shape and height.  The reason is that the dredge handles MUCH more water than a simple sluice box and Much more material.  The shape of the dredges riffles are designed to work with large volumes of water and material.

You may shovel most of the day and be able to shovel just over a yard of material with a regular shovel, with a 1 1/2 or 2" dredge there is no comparison!  It can do five times the work you can.  So compare the sluice boxes with other similar ones.  Start small, the hobby can pay for itself, you can use your gatherings to pay for bigger and better things…

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