Pond Boss Forums POND CONSTRUCTION Soil questions Ball Clay

While looking for clay to seal my leaking pond I ran across Old Hickory Clay Co. http://www.oldhickoryclay.com They are in Tn only about 100 miles from me. They mine clay to use in pottery. They call it Ball Clay. I gave them a call today and they said that their clay is used alot to seal ponds. My soil is about 25% clay and I was thinking that adding some of their clay and mixing well with a tiller may do the trick for a good seal. So is clay just plain clay no matter what or are some better than others? I know bentonite is the best but shipping is way too expensive. I just wanted to get the experts thoughts before I did anything. Thanks

nash, how big is yer pond you want to seal?

my 2c:
there are several types of clays that are distinguished mineralogically and can be distinguished based on the "swelling" properties. i am guessing here, but i would think typical pottery clay is a montmorillonite or kaolinite type clay which does not swell as much as bentonite, but still would work fantastic tilled into yer existing soils at a good percentage...if you already have 25% clay fraction in native soils, i would try and boost that to near 50% along pond bottom and think it would be excellent for pond sealing. i would want a tilled (AND COMPACTED) depth of at least 2 feet.

lets see if you get any other opinions, and good luck.

nashfireman:
I would suggest that you go and get a 5 gallon bucket of this clay and see if it holds water. There are so many types of clay that the best thing is to test it. Mix in the ball clay with your clay about 4 to 1 or so and experiment with the mixture. Add the mixture to a bucket with perforations at the bottom and see how long it will hold water. These self tests may tell you exactly what you need to know without committing to a large cost.