Mesoporous magnesium carbonates (MMCs) constitute a family of magnesium carbonate materials with high specific surface areas. It was first reported in July 2013 by a group of researchers in nanotechnology at Uppsala University. The highest reported surface area of any MMC is 800 m² per gram, which is the highest surface area ever measured for an alkali earth metal carbonate. The average pore size of MMCs can be adjusted by tuning the synthesis conditions. So far, all reported forms of MMCs are anhydrous and X-ray amorphous.