Clay to Glass

This is a interesting discussion. It’ll be interesting to see what else can be done along this line.

One quick observation: glass can certainly contain aluminum in the form of aluminum oxide (alumina). In fact, aluminosilicate glasses have lots of commercial applications due to low thermal expansion and high glass transition temperature (which relates to the max temperature they can be used for structural applications). Most cell phones have aluminosilicate glass screens, which are treated chemically to toughen them.

Technically speaking, the term “glass” refers to the molecular structure of the material and not to a specific chemistry. For example, there are metallic glasses, and some polymers have a glassy phase.

I agree that the vitreous coating that was produced on the clay could be considered a glaze (a glassy protective coating on a ceramic body). A flux applied to the surface of the clay before lasering might reduce the power/time required to produce the glaze.

Apologies for geeking out, but this discussion brought back memories of times spent working with glass for technical applications (fiber optics, mainly).


It’s great to see so many people on this forum with strong material science skills. We are indeed a diverse bunch!

As one who has done a bit of furnace glass most familiar with the “threads” that form from the glass dissolving the sides of the high alumnia tanks and pots it is melted that look like strings of snot and ruin a piece if they get on it, as their low coefficient of expansion (COE) will break the glass. In standard units most window, drinking, and art glass is about 80-100 range. Borosilicate (like probably our laser tubes, Pyrex, most scientific glass etc. ) is around ten I think and most porcelain around one or at least that is the ball park by my understanding, But Alumnia has another property that is good or bad depending on your need is that thickness that holds it to the sides of a pot but makes it hard to manipulate when hot compared to regular commercial soda-silicate glass.

Update - with research I see that Silicate Lava is thicker and more explosive, but it is my impression that it combines with water perhaps better than Aluminum-based lava and that I think is the cause of the diversion of properties.