Sandstone with lots of matrix is known as improperly sorted. If matrix quantities to a lot more than ten % on the rock, it is referred to as a wacke ("wacky"). A perfectly-sorted sandstone (little matrix) with small cement is known as an arenite. Another way to have a look http://sandstone-blocks-lithgow74173.bloggosite.com/15017887/a-secret-weapon-for-sandstone-blocks-mudgee