We have a 2 year old shower/bathroom with stone tile in our basement. There seems to be some water seeping through the floor/wall line at opposite sides of the shower. It is not a lot of water but enough to keep this line wet. We also seemed to have a buildup of what appeared to be white hard calcium like substance around the insides of the drain. Any thoughts as to what this could be

Is the water along an outside wall, concrete wall meeting concrete slab?
Is there any sign of water anywhere else in the basement, especially along the edges?
What is the floor covered with, in the bath and in the rest of the basement?

The deposits in the drain are minerals, mostly calcium, but it's unusual to see them in 2 years, unless you use that shower a lot and also maybe the water in the drain stands at a high level. I assume you have a chrome grid/hair trap over it? Hopefully you have a smaller mesh hair trap over that, a cheap plastic one, because all the hair clogs pretty quickly, and you can't reach any traps or cleanouts.