thanks for your reply
My argument was just what you said if there is clay no matter what percentage it cannot be classed NP
Now our lab has performed particle size analysis on the sample. The sample has 55% fine sand, 35% silt and 10% clay. So the sample is clayey very silty fine SAND. Now the...
Is it possible that a soil sample that can be drawn to 3mm thread when drawn delicately be classed as non plastic. I think all silt soil samples need to be drawn delicately but if they can be drawn to 3mm from a ball then they cannot be classed as non plastic.
Our lab classed it as NP with a...