Hello and thanks for asking. I'm a professional Interior Designer of 26 years and a General Contractor. Also own and operate a design build construction company with my husband. I pretty much design and he builds it. We are blessed with a superior staff of professionals that have mastered their craft for over 25 years. This may appear easy, but it's really takes alot of skill and patience to get a this sort finished look. This is tigers eye stones and I spec'd a black grout, but black grout looks like charcoal grey. Once you seal it will darken a bit. The rocks come on 12x12 sheets, but they are extremely heavy and flimsey. Most rocks are not going to give you a even flush look unless you play with each rock and make sure there is plenty of grout to soften any irregular areas. I designed a mahogany frame around the rocks since the edges are not that attractive unless butted up to something thicker. Blending the sheets of rocks together is also a very important detail if you want it to look continuous if not you will have a significant blank lines of grout defining the sheets. I would definitely possibly try a floor application first and sample the techniques so you are happy with the end results. Installing on walls are very difficult so if your budget allows a qualified professional, I would definitely consider it or save til you can. I would ask your installer for pictures of completed projects and look at the details, level, overlapping, corners, edge details, etc. Ask what materials they use, types of grout, ask if it includes sealer in their quote, etc. Most of our work is on multi million dollar custom homes so this is a must. If you have any more questions please feel free to ask.