Wet precipitation is the process that gives us stalactites and stalagmites, teeth, and many other interesting things. Dissolve the right ingredients in water (wet), mix them together in the right way, and all kinds of solids can form out of the liquid (precipitation). I use it all the time to make nanocrystals like the ones in our teeth, and many other people use it for many other things, but exactly how atoms go from bouncing around a liquid to lining up neatly in a crystal is not entirely understood. In my head it looks like this.