New York is world famous for its high quality bluestone and we are lucky enough to be able to get any color or shape we want.  Bluestone is either sold as thermaled or natural cleft.  Thermaled bluestone is gauged, textured and cut into exacting sizes, which generally makes its appearance formal.  Natural cleft has more texture and shape variations which makes its application better suited for informal styles.  Capping a wall will transform its appearance and can also help to protect the wall from rain and frost.  As far as color, bluestone comes in true blue or shades of grey, brown, tan, rust and lilac with endless supplies of color combinations!