It was first described in 1968 for an occurrence in Dolní Bory, Vysočina Region, Moravia, Czech Republic, and is now known also from Ireland, Japan, and Sweden.

[3] In Brockley on Rathlin Island,[5] Ireland sekaninaite occurs in bauxitic clay within the contact aureole of a diabase intrusive plug.

As an aluminosilicate, the repeated and ordered structure is based on polymerization of one or the other's tetrahedral framework of Si, Al tetrahedra (Yakubovich et al., 2003).

Nearly all analyses show excess of Al and deficiency in Si with respect to tetrahedral components.

The overall substitution of alkalis causes excess in cations found in (K2O, Na2O, CaO), implying that sekaninaite is essentially anhydrous (Grapes et al., 2010).

The varying content of atoms in the octahedral M position has an effect on the orthorhombic unit cell's parameters.

It is shown via crystallographic data that a shift in the iron content leads to a corresponding variance in a and b unit cell parameters (Yakubovich et al., 2003).

As an aluminosilicate/cyclosilicate, the octahedral M-O distances consist of 5 independent tetrahedra form a 3-dimensional anionic framework of ordered and distributed Al3+ and Si4+ cations.

One independent AlO4 and two SiO4 vortex-sharing tetrahedra share oxygen atoms to form six-member rings along the c axis of the unit cell.

The distortion of the orthorhombic unit cell is determined by the chemical composition rather than the degree of ordering in the tetrahedral framework (Yakubovich et al., 2003).

The temperature at which the liquidous phases crystallize in a sequence: mullite + tridymite, followed by sekaninaite and finally fayalite + clinoferrosilite (Grapes et al., 2010).

The increase in the Fe mole fraction of minerals was not related with iron input, but was caused by its redistribution during contact metamorphism (Korchak et al., 2010).

They sampled the poorly developed crystals of the Dolni Bory region, Czechoslovakia, where specimen did not exceed 70 cm.

They are very close analogues with respect to Mg/Fe ratios but vastly different a-, b- and c- parameters (Grapes et al., 2010).

Sekaninaite is classified under the space group Cccm; it is an orthorhombic crystal that is found in series with cordierite (Stanek et al., 1975).

These minerals are more prevalent in paralavas found in: Power River, Wyoming, Ravat area, Tajikistan, Kenderlyk Basin, eastern Kazakhstan and the Djhar basin in India; each differ in sedimentary mineral assemblage and results depend on high-temperature fusion of mixtures of sandstone-siltstone and minor ferruginous components (Grapes et al., 2010).

These Fe-rich paralavas are composed of Fe-olivine, esseneite, dorite, melilite, Fe-cordierite, anorthite, spinel, tridymite, fayalite, magnetite, quartz etc.