To provide an extreme pressure additive which reduces a coefficient of frictional wear for an aqueous lubricant for a metal deformative processing.

Lamellar crystallites having a length (L) in a range between 0.1-100 m, a width (l) in a range between 0.5-30 m and a thickness in a range between 5-200 nm, comprise a stack of organic phases (O) and aqueous solutions (A) in the sequence O/[A/O]n, wherein the stack has a thickness between 5-200 nm, the organic phases comprising (i) at least an acid selected among saturated or unsaturated carboxylic acids containing at least 5 carbon atoms, acidic phosphate esters of formula (RO)x-P(=O)(OH)x' wherein R is a hydrocarbon radical, optionally polyalkoxylated, x and x' being equal to 1 or 2, provided that the sum of x and x' is equal to 3, the acid being optionally neutralized by an organic or mineral base, and at least a metal in the form of a multivalent ion, or (ii) at least a polyoxyalkylene block polymer having a cloud point preferably ranging between 30-90C, and a method for obtaining them.