Mossbauer investigations of the unequilibrated chondrite ALHA 77278 are reported. The chondrules studied are found to contain the silicates olivine and pyroxene, and one of the chondrules furthermore contains kamacite (b.c.c. iron-nickel alloy). The investigations of a powder mixture of chondrules and matrix show that the meteorite, besides the silicates and the kamacite, contains troilite and taenite (f.c.c. iron-nickel alloy). The taenite is found as a ferromagnetic, totally disordered alloy containing more than 40% nickel. The results are discussed within the framework of the theories about the condensation sequence of minerals in the early solar system.

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A new high-spin isomer ''2Hf has been produced by irradiation of isotopically enriched GYb with m particles. To investigate its decay, Ge(Li) p-ray spectra, Si(Li) conversionelectron spectra, and NaI(Tl)-Ge(Li) and Ge{Li)-Ge(Li) y~c oincidence spectra have been recorded. y rays with energies 122.7, 146.2, 169.8, 192.8, 217.0, 236.6, 257.5, 268.9, 316.0, 362.6, 409.8, and 453.7 keV have been attributed to the decay of the isomer. These decay with a half-life of (29+1) day. The coincidence measurements establish that the quanta with energies 122.7 through 236.6 keV are in cascade, while the y rays with energies 268.9 through 453.7 keV represent crossover transitions within a rotational band with levels up to I= g built on the n~Hf ground state. The rotational-model quantity ig&gz)2/QO2 has been derived from y intensity measurements of the cascade and crossover transitions. It is constant within the experimental error for all members of the band. The values for the gyromagnetic ratios g& = -0.202 + 0.027 and g&= 0.160 + 0.014 have been deduced.

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