CuSO4 (Copper sulfate) is a chemical can everyone buy in almost every drugstore or on the internet. I bought like 1 kg, it is quite cheap, but you dont need so much.. Buy it in powder form.
Growing crystals from CuSO4 is well known thing. I've made many of them and i was thinking how if would look like if i try to grow them on an ordinary rock. And here it is...beauty:*
Procedure is very simple and it is reversible process....
!!! This chemical is toxic !!! Wear protection !!!
!!! Don't breathe it, touch it too much and certainly don't eat it no matter how tasty it looks !!!
Step 1: Growing solution
Pour it into a glass jar or something with a smooth surface so crystal will not grow on walls but mostly on a rock. (heat the jar first)
2. Then Copper Sulfate. Add. Mix until it dissolves. Add. Mix until it dissolves. Add. Mix until it dissolves.
Until it is not dissolving in a water anymore. And do it outside! ;)
Step 2: Rock and spot
3. Put a rock into the solution and the jar place in a dark spot (not nessesary absolute darkness, i placed it in a room that was not used). , Don't breathe vapors from it -> basement is perfect.
...And leave it there. Do not disturb it. Don't even think about it.
* The rock should have diverse surface, somewhere smooth, somewhere not.
It has to be hard,tough,real rock! :D