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Nickel is one of the metals that can form Tutton's salts. The singly charged ion can be any of the full range of potassium, rubidium, cesium, ammonium , or thallium. As a mineral the ammonium nickel salt, 2Ni2 · 6 H2O, can be called nickelboussingaultite. With sodium, the double sulfate is nickelblödite Na2Ni2 · 4 H2O from the blödite family. Nickel can be substituted by other divalent metals of similar sized to make mixtures that crystallise in the same form.
Nickel forms double salts with Tutton's salt structure with tetrafluoroberyllate with the range of cations of ammonia, potassium, rubidium, cesium, and thallium.
Anhydrous salts of the formula M2Ni23, which can be termed metal nickel trisulfates, belong to the family of langbeinites. The known salts include 2Ni23, K2Ni23 and Rb2Ni23, and those of Tl and Cs are predicted to exist.
Some minerals are double salts, for example Nickelzippeite Ni26310 · 16H2O which is isomorphic to cobaltzippeite, magnesiozippeite and zinczippeite, part of the zippeite group.