The very first glass work I did was to cast a cube. I had bought a bunch of glass blocks off of Craig’s list, the kind you use for windows. These are really cool, and pretty cheap if you buy them as junk.
I broke up the glass with a hammer, then I made a simple cubicle mold and placed it all in the kiln to fire.
The result is….interesting… There are some things I like and some things I don’t. One problem is that the glass is discolored. Even though it was clear before, now it is a little more cloudy, with a beige tinge.
The other feature is that the glass is heavily veiled, meaning that you can see waves an surfaces where the glass chunks melted together. This gives the glass a textured look with depth. I like it, but most people don’t.
It was a learning experience. In retrospect, I’d recommend against using recycled glass of unknown origin. You will probably get effects like this that are hard to control.