Have you ever worked with concrete? You probably know it is a very versatile material. It can’t be used to make long extensions or flexed much — it is not strong that way. But it can be used to put weight on top of.
It is also inexpensive and can be shaped into almost any arrangement.
Mostly it is used as a utilitarian material, but it can also be used for furniture, counters, vases, bowls, sconces, and other objects.
What you need is cement and water. That’s all. The water turns the cement powder into a soupy fluid, which turns into solid hard cement when it dries (over the course of a few hours to a day or so, but it continues to harden for a very long time).
The texture of concrete can be modified greatly. You can pour straight concrete and get a smooth, brittle, slate-like piece. You can add rough sand, fine sand, colored sand, white or black sand. You can add dye or other coloring. You can add gravel or other larger material.
When it’s finished, you can sand it, polish it, cut into it.