Process for the preparation of an aqueous solution comprising at least one earth alkali hydrogen carbonate, the process comprising the steps of: a) providing water, b) providing at least one substance comprising at least one earth alkali carbonate and optionally at least one earth alkali hydroxide in a minor amount in respect to the earth alkali carbonate, the at least one substance being in a dry form or in an aqueous form, wherein the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide is selected from the group comprising marble, limestone, chalk, half burnt lime, burnt lime, dolomitic limestone, calcareous dolomite, half burnt dolomite, burnt dolomite, and precipitated calcium carbonate, c) providing CO 2, d) combining either: (i) the water of step a), the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide of step b) and the CO 2 of step c), or (ii) the water of step a) and the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide of step b) in order to obtain an alkaline aqueous suspension of the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide, and subsequently combining the alkaline aqueous suspension with the CO 2 of step c) in order to obtain a resulting suspension S having a pH of between 6 and 9, the resulting suspension S containing particles, e) filtering at least a part of the resulting suspension S that is obtained in step d) by passing the resulting suspension S through a filtering device in order to obtain the aqueous solution comprising at least one earth alkali hydrogen carbonate, wherein the aqueous solution obtained after filtration has a turbidity value of lower than 1.0 NTU and has a calcium concentration, as calcium carbonate, from 50 to 650 mg/l, wherein the particles of the resulting suspension S that is obtained in step d) represent a total particle surface area (SSA total) that is > 20 000 m 2 /tonne of the resulting suspension S, and wherein the resulting suspension S that is obtained in step d) has a solids content in the range from 1 to 35 wt.-%, based on the total weight of the resulting suspension S, with the proviso that an addition of the CO 2 of step c) does not take place before an addition of the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide of step b), and wherein the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide of step b) has a specific surface area in the range of 0.01 to 200 m 2 /g. a) providing water, b) providing at least one substance comprising at least one earth alkali carbonate and optionally at least one earth alkali hydroxide in a minor amount in respect to the earth alkali carbonate, the at least one substance being in a dry form or in an aqueous form, wherein the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide is selected from the group comprising marble, limestone, chalk, half burnt lime, burnt lime, dolomitic limestone, calcareous dolomite, half burnt dolomite, burnt dolomite, and precipitated calcium carbonate, c) providing CO 2, d) combining either: (i) the water of step a), the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide of step b) and the CO 2 of step c), or (ii) the water of step a) and the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide of step b) in order to obtain an alkaline aqueous suspension of the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide, and subsequently combining the alkaline aqueous suspension with the CO 2 of step c) in order to obtain a resulting suspension S having a pH of between 6 and 9, the resulting suspension S containing particles, (i) the water of step a), the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide of step b) and the CO 2 of step c), or (ii) the water of step a) and the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide of step b) in order to obtain an alkaline aqueous suspension of the at least one substance comprising at least one earth alkali carbonate and the optional at least one earth alkali hydroxide, and subsequently combining the alkaline aqueous suspension with the CO 2 of step c) e) filtering at least a part of the resulting suspension S that is obtained in step d) by passing the resulting suspension S through a filtering device in order to obtain the aqueous solution comprising at least one earth alkali hydrogen carbonate, wherein the aqueous solution obtained after filtration has a turbidity value of lower than 1.0 NTU and has a calcium concentration, as calcium carbonate, from 50 to 650 mg/l,