 So clays may exist within a matrix of soil particles and it might look something like this where you have large particle grains Indisperse with with a range of clay sheets now if you take that material and you remold it what you might be left with is Parallel alignment of these clay sheets, so they all might start aligning with each other in which case you might define Within that remolded material preferential shear pathways or planes of weakness so This remolded behavior of clays is really quite important to understand and we define it through something called sensitivity so soils with a high sensitivity are really susceptible to Large changes in strength due to remolding so Most clays have a sensitivity of one to four and Sensitivity is defined through this equation So let's call it just s for sensitivity is equal to the the peak strength of the undisturbed material divided by The strength of the remolded so a larger sensitivity means that the The peak strength is so much more than the remolded strength So if you do a test on an undisturbed Sample of clay and you get one the strength value that might not be the strength That might be apparent within the field if the soil has been remolded So that's why it's important to understand and most clays have a sensitivity of equal to well between one and four so the Undisturbed strength is up to four times greater than the remolded strength Sensitive clays might have sensitivity between four and eight and That's sensitive now extra sensitive clays might have a Sensitivity of between eight and sixteen Now in a very special case we have something called quick clays or marine clays that have sensitivity of up to a hundred that means the the undisturbed Materials a hundred times stronger than the disturbed material now quick clays or marine clays form When a Clays laid down in a marine environment or a solution of higher ionic strength where the Cations in the in the solution and move into the clay and they create Extra strength within the material now if you take that that sediment that's been laid down and you bring it to the surface And you subject it to weathering with rainwater the rainwater starts to dissolve some of that those cations out of the material So you what you're and end up with is a almost like a house of cods. So you have a Clay where the the strength of the materials being removed the cations have been removed and they're just waiting to Collapse in some ways. So that's you can see Videos of really dramatic Failures due to to marine clays and I've touched linked to to those on my my website Which is has a link below so take a look at those and that's for really highly sensitive clays