Yes, use epoxy.
It will be rock hard.
Add water to it.
With superglue
Yes, certain types of clay can dissolve in water. These types of clays are not fired, non oil based clays, but natural and air dried clays.
A dried clay cannot be classified as a rock
"Caked clay" refers to clay that has dried out and hardened, typically forming a hard layer on the surface. It can be difficult to work with and often requires rehydration to make it pliable again for sculpting or pottery.
nope, its made up of plasticine (which is non-toxic)
Dried clay
Yes, you can use acrylics on clay after the clay has been dried.
Yes, use epoxy.
It will be rock hard.
Add water to it.
no.
desert gravel is just dried clay
With superglue
sun dried bricks