The electron absorption-, photoluminescence- and electron paramagnetic-resonance spectra of Mn³⁺ in red beryl from Wah Wah Mountains (Utah USA) and of pink- and purple vesuvianite from Jeffrey Mine (Asbestos, Canada) were measured at room- and low temperatures. The crystal field stabilization energies are equal to 130.9 kJ/mol for the red beryl, and 151.5–158.0 and 168.0 kJ/mol for for the pink- and the purple vesuvianite, respectively. The red photoluminescence of Mn³⁺ was not intensive either at room- or at low temperatures. The high Mn content in the crystals caused the emergence of an additional emission band and short photoluminescence-decay lifetimes. The latter are only 183 μs for beryl and 17 μs for vesuvianite.

A FePt-based hard-magnetic nanocomposite of exchange spring type was prepared by isothermal annealing of melt-spun ${\text{Fe}}_{52}{\text{Pt}}_{28}{\text{Nb}}_2{\text{B}}_{18}$ (atomic percent) ribbons. The relationship between microstructure and magnetic properties was investigated by qualitative and quantitative structural analysis based on the x-ray diffraction, transmission electron microscopy, and ${}^{57}\text{F}\text{e}$ Mössbauer spectrometry on one hand and the superconducting quantum interference device magnetometry on the other hand. The microstructure consists of $\text{L}{1}_0\text{-FePt}$ hard-magnetic grains (15–45 nm in diameter) dispersed in a soft magnetic medium composed by A1 FePt, ${\text{Fe}}_2\text{B}$ , and boron-rich (FeB)PtNb remainder phase. The ribbons annealed at $700°\text{C}$ for 1 h exhibit promising hard-magnetic properties at room temperature: ${\text{M}}_{\text{r}}/{\text{M}}_{\text{s}}=0.69$ ; ${\text{H}}_{\text{c}}=820\text{kA}/\text{m}$ and ${\left(\text{BH}\right)}_{\text{max}}=70\text{kJ}/{\text{m}}^3$ . Strong exchange coupling between hard and soft magnetic phases was demonstrated by a smooth demagnetizing curve and positive $\delta \text{M}$ -peak in the Henkel plot. The magnetic properties measured from 5 to 750 K reveals that the hard characteristics remains rather stable up to 550 K, indicating a good prospect for the use of these permanent magnets in a wide temperature range.