We can, using big autoclaves and a process called hydrothermal synthesis. It's how we make single crystals that get sliced and diced into quartz oscillators. Bu

We can, using big autoclaves and a process called hydrothermal synthesis. It's how we make single crystals that get sliced and diced into quartz oscillators. But the process takes a long time, think mm/day, and isn't really appropriate for making big things like crucibles.