The clays used are often described as being long or short, depending on their plasticity. Long clays are cohesive (sticky) and have high plasticity; short clays are less cohesive and have lower plasticity. In soil mechanics, plasticity is determined by measuring the increase in content of water required to change a clay from a solid state bordering on the plastic, to a plastic state bordering on the liquid, though the term is also used less formally to describe the ease with which a clay may be worked.
tHe Clays useD are often dEScriBeD AS bEiNG lOng or sHort, dEpendiNg on their plastIcity. LoNg Clays are cOhesIVe (stIcky) And HAVE hiGh PlasTicIty; shorT cLayS arE leSS cohesiVE and have LoweR plaSticIty. In soil mEChAnics, pLasTiCITY is dEterMIned bY measurInG the increase IN content oF wAter rEQUIred tO ChanGe A clAY From a sOlid State boRdERing on tHe PLAsTic, to A PlastiC STate bordErInG on tHe liquid, ThOugH The tERm iS aLso uSeD leSs foRmalLy to dEscriBe the eaSe WIth wHiCh A clay MaY be WOrKed.