Sodium Silicate Technique

Here’s a video for those of you looking to try out a new surface technique on your clay projects. It’s likely that you’ve seen this before, where a piece of pottery has a surface that resembles dry, cracked leather. The look is achieved by using sodium silicate during the building process and can be amplified by using underglazes, stains, or glazes that break well over texture. This technique is not limited to work made on the potter’s wheel, it’s just easier to demonstrate. For any clay project this can be a fun way to embellish the surface while [literally] stretching the walls of your work a little further! To achieve this look the sodium silicate solution is brushed onto the wet clay surface and dried with a heat gun (or hair dryer). Once the dry shell has formed, push out from the inside and watch the cracks emerge. Results will vary depending on the clay body used, wall thickness, and wetness or dryness of the clay but that’s the fun part of experimentation! Blue and orange underglazes were applied and dried before the sodium silicate in this video so that the results can be easier seen. The second form in this video demonstrates what can happen if you dry your piece too much, resulting in a difficult stretching, larger cracks, and a rather out-of-round approach! It is important to remember that you are only drying the outer surface where solution has been applied, not the whole piece! Sodium silicate can be purchased online by the pint and should last quite a while for the solo-maker - a little bit goes a long way. In other applications this product is utilized as an aid to the drying strength of clay/glaze, while in another realm of ceramics, called slip-casting, it’s used to deflocculate clay slip. It is a water soluble product, non-flammable and non-toxic, but can cause irritation to the skin and eyes so be careful when applying. When trying this technique, please make sure to wash brushes with hot water and to clean any surfaces that may have been dripped on. This solution will dry and be difficult to remove, sometimes needing to be chipped away, and nobody needs that mess. We’d love to see your results if you give it a try, be sure to share a photo and tag us on social media!