[4][5] Meridianiite is a naturally occurring mineral species found on Earth in a variety of environments including sea ice, crusts and efflorescences in coal/metal mines, cave systems, oxidized zones of sulfide deposits, salt lakes/playas and Antarctic ice-cores.

[8][6][7] Meridianiite can incorporate large proportions of other divalent cations (whose sulfates themselves do not seem to form an undecahydrate) as solid solution, without changes to its structure.

[7] At pressures of about 0.9 GPa and at 240 K, meridianiite decomposes into a mixture of ice VI and the enneahydrate MgSO4·9H2O,[9] In 1837 by C. J. Fritzsche described what he interpreted as magnesium sulfate dodecahydrate, based on the weight loss during dehydration to the anhydrous salt.

[2] Meridianiite has been found to occur on the surface of the ice layer formed in winter over the ponds known as Basque Lakes, in Canada.

[4] Meridianiite has also been detected in sea-ice collected in winter from the saline Lake Saroma in Japan, as well as in ice cores from Dome Fuji station, Antarctica, near the summit of the east Dronning Maud Land plateau.

The now empty angular holes are interpreted as being cavities once filled by a highly soluble mineral species, most likely a magnesium sulfate.