Mutinaite


Mutinaite		\|Na₃ Ca₄ (H₂O)₆₀\| [Al₁₁Si₈₅O₁₉₂]

Morphology:
	Subspherical aggregates (up to 1.8 mm) of tiny radiating lath-like fibers or as aggregates of transparent tabular crystals.

Physical properties:
	Cleavage: {100} good. Hardness: 3 - 4. Density: 2.14 (obs) gm/cm³. Luster: vitreous. Streak: white.

Optical properties:
	Color: colorless to white; colorless in thin section. Biaxial (-). α = 1.485, β= 1.487, γ = 1.488, δ = 0.003, 2Vx = 70°. O.A.P \|\| (100).

Crystallography:
	Unit cell data: a 20.201, b 19.991, c 13.469 Å, Z = 1, Space Group Pnma (Vezzalini et al. 1997).



Name:
	Mutinaite was named and described by Galli et al. (1997). The type locality is in the Ferrar dolerite, exposed in the southwest crest, just under Mt. Adamson, Antartica. The name is for Mutina, the ancient Latin name of Modena, Italy, recognizing the Department of Earth Science at the University of Modena as an active center for zeolite research.

Crystal structure:
	The framework topology (MFI) of mutinaite (Vezzalini et al. 1997) is the same as that of the synthetic zeolite ZSM-5 (Olson et al. 1981). Mutinaite, however, has a much higher content of Al than any of the ZSM-5 frameworks, for which the structure has been refined. The pentasil nature of the framework can be seen in a sheet parallel to 010 (accompanying figure). The building units of this sheet are the mfi (5⁴5⁴), cas (5²6²), and tes (5⁴) polyhedra.
	These units, linked by sharing of edges or faces, form 10-membered rings. The resulting framework contains two intersecting channels, one parallel to [010] form the 10-ring openings of the 010 sheet, and the other is sinusoidally parallel to [100]. The effective diameters of the 10-rings of the [010] channel are 6.1 x 4.6 Å, and that of the 10-rings of the [100] sinusoidal channel, about 5.1 Å. The narrow range of T-O distances, 1.587-1.618 Å, is compatible with a disordered Si-Al distribution (Vezzalini et al. 1997). Although 17 non-framework sites were located within the channels all have such low electron densities that partial cation occupancy could not be distinguished from H₂O molecules. One site, tentatively assigned to Ca²⁺ (red), is not coordinated with any framework oxygen. The dehydration behavior of the synthetic counterpart of mutinaite, zeolite ZSM-5, was investigated by van Koningsveld (1990) and Precisvalle et al. (2023). The structural deformations induced by pressure in mutinaite were studied by means of complete Rietveld structural refinements (Quartieri et al. 2012).

Chemical composition:
	The only analysis for mutinaite is given by (Galli et al. 1997). T_Si value of 0.883 is the highest of any known natural zeolite. All synthetic analogs of multinaite (ZSM-5 and silicalite) have even higher silica contents.

Occurrences:
	Mutinaite has been found in only one occurrence, vesicles and cavities in the Jurassic Ferrar dolerite of Mt. Adamson, Northern Victoria Land, Antarctica. It is associated with other zeolites, mordenite, heulandite, erionite, phillipsite, stilbite, levyne, epistilbite, tschernichite, boggsite, gottardiite, ferrierite, and cowlesite, as well as quartz, cristobalite, apophyllite, gypsum, and calcite. Galli et al. (1997) suggest that the rare, disordered, high-silica zeolites in this association must have formed under special conditions, such as rapid environmental cooling during crystal growth.

References:
	Galli, E., Vezzalini, G., Quartieri, S., Alberti, A., and Franzini, M. (1997) Mutinaite, a new zeolite from Antarctica: the natural counterpart of ZSM-5. Zeolites. 19, 318-322. Olson, D.H., Kokotailo, G.T. & Lawton, S.L. (1981) Crystal structure and structure-related properties of ZSM-5. J. Phys. Chem. 85, 2238-2243. Precisvalle, N., Mancinelli, M., Ardit, M., Beltrami, G., Gigli, L., Aloise, A., Catizzone, E., Migliori, M., Giordano, G., Guidi, V. and Martucci, A. (2023) Temperature Induced Monoclinic to Orthorhombic Phase Transition in Protonated ZSM-5 Zeolites with Different Si/Al Ratios: An In-Situ Synchrotron X-ray Powder Diffraction Study. Crystals, 13(6), 979. Quartieri, S., Arletti, R., Vezzalini, G., Di Renzo, F. and Dmitriev, V. (2012) Elastic behavior of MFI-type zeolites: 3–Compressibility of silicalite and mutinaite. J. Solid State Chem., 191, 201-212. Van Koningsveld, H. (1990) High-temperature (350 K) Orthorhombic Framework Structure of Zeolite H-ZSM-5. Acta Cryst. B, 46, 731–735. Vezzalini, G., Quartieri, S., Galli, E., Alberti, A., Cruciani, G., and Kvik, Å. (1997) Crystal structure of the zeolite mutinaite, the natural analog of ZSM-5. Zeolites. 19, 323-325. Updated: October 2025.