Method for the preparation of an aqueous slurry of calcium hydroxide with a dry content of at least 40% by weight, having a content in calcium hydroxide particles between 40 to 60% by weight, based on the total weight of the aqueous suspension, the viscosity of the said aqueous slurry measured by a Brookfield DVIII viscometer at 10 RPM being between 25 and 1,000 mPa.s at 20°C, including the steps consisting of: a) providing of a specific volume of an aqueous solution, b) providing of a specific quantity of powdered calcium hydroxide, c) providing of a specific quantity of a copolymer consisting: - of methacrylic acid monomers and/or any of its salts, - possibly of acrylic acid monomers and/or any of its salts, - monomers with the formula: R-X-R' according to which: R represents a polymerizable unsaturated group, notably acrylate, methacrylate, methacrylurethane, vinyl or allyl, R' represents hydrogen or an alkyl group with from 1 to 4 carbon atoms, X represents a structure with n unit(s) of ethylene oxide EO and m unit(s) of propylene oxide PO, arranged randomly or regularly, m and n are 2 non-zero integers and are between 1 and 150, d) to at least a part of said aqueous solution, at least a part of the quantity of the said copolymer is added under agitation, e) to the aqueous solution of step d), at least a part of the said quantity of the said calcium hydroxide is added under agitation, f) a homogeneous shearing level greater than 50,000 s -1 is applied to the mixture resulting from step e), g) possibly, in the course of step f), the remaining quantity of the said copolymer and/or of the said calcium hydroxide is added. a) providing of a specific volume of an aqueous solution, b) providing of a specific quantity of powdered calcium hydroxide, c) providing of a specific quantity of a copolymer consisting: - of methacrylic acid monomers and/or any of its salts, - possibly of acrylic acid monomers and/or any of its salts, - monomers with the formula: R-X-R' according to which: R represents a polymerizable unsaturated group, notably acrylate, methacrylate, methacrylurethane, vinyl or allyl, R' represents hydrogen or an alkyl group with from 1 to 4 carbon atoms, X represents a structure with n unit(s) of ethylene oxide EO and m unit(s) of propylene oxide PO, arranged randomly or regularly, m and n are 2 non-zero integers and are between 1 and 150, - of methacrylic acid monomers and/or any of its salts, - possibly of acrylic acid monomers and/or any of its salts, - monomers with the formula: R represents a polymerizable unsaturated group, notably acrylate, methacrylate, methacrylurethane, vinyl or allyl, R' represents hydrogen or an alkyl group with from 1 to 4 carbon atoms, X represents a structure with n unit(s) of ethylene oxide EO and m unit(s) of propylene oxide PO, arranged randomly or regularly, m and n are 2 non-zero integers and are between 1 and 150, d) to at least a part of said aqueous solution, at least a part of the quantity of the said copolymer is added under agitation, e) to the aqueous solution of step d), at least a part of the said quantity of the said calcium hydroxide is added under agitation, f) a homogeneous shearing level greater than 50,000 s -1 is applied to the mixture resulting from step e), g) possibly, in the course of step f), the remaining quantity of the said copolymer and/or of the said calcium hydroxide is added.