Martianware Pottery Clay

Brian HartmanFeb 12, '2112 comments

Experimenting with Martianware Pottery Clay

MARS. The newest frontier. A place of great discovery and a greater number of questions. Was there once life on Mars, was there water, can humans live there? In my humble opinion the most important question is often left out: is there clay on Mars and can I throw with it? With the Opportunity mission finding that Mars most likely hosted water at one point, I am hoping that finding clay on Mars is inevitable. This is my greatest hope for Perseverance, the new Mars rover which is landing on February 18th, 2021. Perseverance is going to take many solid samples and see if Mars is suitable for human life.

To celebrate the anticipation of finding clay on Mars we are releasing our new clay body on landing day. Our new clay body has been synthesized to mimic the soil of Mars if we were to mix a clay from native materials. Using the data provided by NASA and many research projects based on Mars data, we have compiled an average chemical composition to create this new clay body. Seattle Pottery Supply is proud to announce Martianware: a clay body that is truly out of this world. 

What is Martianware clay?

Martianware clay is a clay body built to mimic the chemical composition of the surface of Mars, based on data provided by NASA, Mars research projects, and synthetic Mars soils. Martianware, to our best ability, is the native clay you would find on the surface of Mars, provided that enough water would be present.


How is it similar to Mars?

After a lot of research and data crunching, we found a chemical composition for Martian soil that we were able to   reverse engineer into a clay body. It is not only chemically similar in the macro chemicals (SiO2, Al2O3, MgO, Na2O, etc.) but also the minor chemicals found in Mars solid (Cr2O3,Ni2O, MnO). It also sources minerals, such as Olivine, that are found in abundance on Mars, in the clay body.


How is it different from Mars?

I would love to tell you this is exactly the same as Mars soil, but in the end soil is soil and clay is clay. We can not use soil for clay and soil lacks necessary components to make a clay body work. It's why you can’t make mud into a beautiful mug in the same way as a manufactured clay body. This means that we could not source all the materials from minerals found on Mars, since much of the soil is made of different basalts. We like to believe that if clay were to be found, based off the current data of Martian soil, what we have would be very close to that. What we have produced is an average combination of Martian soils - we did not take a single sample and mimic that one, but we pulled from many data points to create a composite. This was done because when Seattle Pottery Supply eventually expands to its new Mars location, this is most likely what we would be producing.


What makes Martianware clay so special?

Besides being built to mimic the surface Mars, this clay takes chemicals typically not found in clay. We did not know how this would affect the clay body and whether or not this would live in a kiln. What ends up happening is something we like to call “self-glazing clay.” Due to the abundance of soluble salts in the clay body, a crust is formed and during firing the salts precipitate to the surface and create a glassy outer layer. Our team has been completely obsessed with this effect and the fired results of the clay body.


What makes you excited about this clay body?

This body, in my opinion, could help usher clay into a new era we have yet to discover. For many years with glaze technology and kilns advancing we as potters have focused on pushing glazes to a limit and learning to control them in a way our ancestors were not able to. We see this reflected in purposefully crawling glazes, colorant stains, crystal glazes, controlled reductions, etc. We have only simply begun to push our clay bodies to new extents. It is time for potters and artists to push clays to limits it has never gone, and using the rich diversity of materials the Earth and other planets have to offer to create clays that do incredible things, and things we never thought clay could do.


What can I use Martianware clay for?

Martianware clay is great for many applications, such as throwing, sculpting, tile making, and hand building. We have only tried a handful of things with this clay in our time of experimentation. We hope that you take this clay to greater heights than we could ever imagine.


Because it self glazes, do I have to glaze it?

If you are hoping to make drinkware, tableware, or a surface for anything being consumed I always recommended a glaze. It is the safest thing to do for yourself, customers, and loved ones. However, due to the soluble salts in the clay your traditional glazes may act a little weird. As always we recommend experimentation and test tiles!


Is there anything special I need to do with this clay?

When you fire this clay body we recommend to fire on a light dusting of alumina hydrate or kiln wadding. This will help prevent any possibility of plucking that we have found can occur. Treat this clay like it is in a soda firing since that is what the glaze is coming from, really hot salt. Make sure to use wadding or alumina hydrate underneath the clay when firing to make sure there is no sticking to kiln shelves. 

We encourage experimenting with this clay and recommend keeping it below cone 1 when fired. In order to achieve the "self-glazing" effect, you only need to fire it once. Any firings after bisque, proceed with caution. 

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Comments (12)

Rob Rigutto on May 26, '22

Do you know the thermal expansion of the fired Martian body (fired to Cone 04) ?
Thank you

Paul Campbell on Dec 10, '21

Fabulous clay.
After playing with it a few times, I can’t imagine a raw clay that I get more pleasure from. The anticipation of the end result is pretty exciting.

Umar Farooque Musthafa on Aug 23, '21


George Rutherford on Apr 25, '21

A friend gave me some of your Martianware. Can I fire it along with a regular bisque firing to cone 06?

Paula Rey on Mar 20, '21

Oh this is fabulous, way to go with all your new calculations..can’t wait to get my hands on some..

Yvonne Apol on Mar 19, '21

Would like to order this clay. How do I do that?

Lorraine L Wolaver on Mar 1, '21

You recommend using wadding under pots – can I make this with alumina oxide? I’ve not fired anything with wadding before so I’m not sure how to proceed :)

DougVan Beek on Feb 28, '21

SO SO SO cool!!!! Where is the link to order????

Vivian on Feb 25, '21

Oooh! My two passions in one – Space and Earth! Can’t wait to throw with it. Great idea. Thanks!

Constance Kuhn on Feb 23, '21

What cone do you fire this to?

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