The invention relates to a dental mill blank comprising a pre-sintered porous zirconia material, the porous pre-sintered zirconia material showing a N2 adsorption of isotherm type IV according to IUPAC classification, the porous pre-sintered zirconia material having a Vickers hardness from about 25 to about 150, the dental mill blank comprising means for reversible attaching it to a machining device. The invention also relates to a process of producing a zirconia dental article comprising the steps of providing a dental mill blank comprising a porous pre-sintered zirconia material, placing the dental mill blank in a machining device, machining the porous zirconia material and to a dental article obtained by such a process.