This is not so. In most projects the design of the project is based upon an evaluation of ground conditions which is established from the description of samples and natural or excavated outcrops, and thence the testing of chosen materials. Most testing is undertaken on materials which represent the various bodies identified by visual inspection. Thus correct identification is of vital importance and is the firm basis on which all geotechnical models are founded. Many significant engineering mishaps have originated in poor description, and the inaccurate description of ground conditions is a common cause for contract claims.