Monday, August 13, 2012

Making Red Slip and White Slip

A couple of days ago I made this strip coiled vase. I decided to add some stripes of red slip. I used a thin brush and went around and around with the red clay slip in the seams. This red clay is Navajo Wheel I got from IMCO clay on the West coast when I lived there. It fires a beautiful reddish brown color. I forgot I still had a little of this clay left so I decided to mix some up to use on a few of my towers because I know this clay will bond with the white clay unlike the Florida clay.

When I was in college studying pottery we mixed up our slip using wet clay every time we got to class. Later I learned mixing slip from dry clay is much much easier and the slip is much smoother. Here's how I mixed up some red and some white slip.

 I start with some very dry clay and I put it in a plastic bag and beat it into as small a pieces as I can.

 Then I put the clay in a bowl. I like using these stainless steel bowls because they won't stain with the color of the clay. I cover the clay with water and just a little extra. I don't want to add too much water because I don't want my slip too thin. I can always add more water.  If I plan to add mason stains to the white slip I use distilled water. If I am using the slip for joining seams I just use tap water. Don't stir the clay until it absorbs the water.

Just for fun hold the bowl up to your ear after adding the water, you can hear the water being absorbed into the clay. I know, I'm easily entertained, but there is something kind of magic about hearing the air in the clay being displaced by the water being absorbed. I set the bowl aside for about two hours or longer without stirring or mixing it.

 Later I come back and stir up the wet clay. This time the clay pieces were small enough I didn't have to use my hand held mixer to mix the clay, just a spoon. If I am using the slip for mixing with mason stains I would strain it to be sure all the lumps were out of it. For joining seams I don't strain it. This particular white stoneware clay mixes up nice and smooth. Some clays with more grog may have to be strained.

Here's the slip in my slip container. The white slip may be a little thick but I can always add more water.

 I did the same thing for the red clay. First I chopped up the dry clay and then put it in a bowl, covered with water, then set aside for two hours or more, then stirred it up. Again I didn't have to use a mixer with the red clay.

Thanks for reading and for all your comments.


  1. Hello Linda;
    It is so intriguing learning about all the various processes involved in the production of ceramics. Never having made anything from any kind of clay we are enthralled by all this chemistry which becomes Art!

  2. Oh Linda, you touched my heart with listening to clay bubbles as it reconstitutes into slip. What a fun and unique experience!

  3. very interesting, Linda, thanks for the lesson.

  4. Very interesting and what a funny vase, me like *smile*.


  5. Hi Jane and Lance, thanks, I guess working with clay is a lot like cooking, the chemistry and mystery of it all, will it turn out, so much fun and a challenge too.

    Hi Barbara, thanks, I can't remember when I first heard the noise emanating from the bowl of slip slaking but it made me smile with wonder, sometimes it's the little things.

    Hi Gigi, thanks, I always hope my posts can help someone as other's posts have helped me along the way.

    Hi Elna, thanks, clay is an exploration and so much fun, it's ok to do what you feel and enjoy the process, hugs to you too.

  6. This comment has been removed by the author.

  7. I really like your strip coiled vase and the way you decorated it with red slip. I enjoy that fizzing sound of dry clay of life's little pleasures, lol.

  8. Hi Mark, thanks, yes one of the small pleasures of clay making, Ha. I hope the red clay stays that color, that rich red.


I love suggestions, questions, critiques, thanks for your comment