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A natural barioferrite, BaFe123+O19, from a larnite-schorlomite-gehlenite vein of paralava within gehlenite hornfels of the Hatrurim Complex at Har Parsa, Negev Desert, Israel, was investigated by Raman spectroscopy, electron probe microanalysis, and single-crystal X-ray analyses acquired over the temperature range of 100-400 K. The crystals are up to 0.3 mm x 0.1 mm in size and form intergrowths with hematite, magnesioferrite, khesinite, and harmunite. The empirical formula of the barioferrite investigated is as follows: (Ba0.85Ca0.12Sr0.03)(Sigma 1)(Fe10.723+Al0.46Ti0.414+Mg0.15Cu0.092+Ca0.08Zn0.04Mn0.032+Si0.01)(Sigma 11.99)O-19. The strongest bands in the Raman spectrum are as follows: 712, 682, 617, 515, 406, and 328 cm(-1). The structure of natural barioferrite (P6(3)/mmc, a = 5.8901(2) angstrom, c = 23.1235(6) angstrom, V = 694.75(4) angstrom(3), Z = 2) is identical with the structure of synthetic barium ferrite and can be described as an interstratification of two fundamental blocks: spinel-like S-modules with a cubic stacking sequence and R-modules that have hexagonal stacking. The displacement ellipsoids of the trigonal bipyramidal site show elongation along the [001] direction during heating. As a function of temperature, the mean apical Fe-O bond lengths increase, whereas the equatorial bond lengths decrease, which indicates dynamic disorder at the Fe2 site.