New magnetically ordered CoBO$_3$ crystal

Crystals of a new CoBO$_3$ compound were synthesized from a solution in melt. According to the X-ray diffraction data, CoBO$_3$ crystallizes in the calcite structure with lattice parameters $a_H=4.631\pm0.005$, $c_H=14.51\pm0.01$Å. Measurements on SQUID and vibrating-coil magnetometers suggested that CoBO$_3$ is a magnetically ordered crystal with a saturation magnetization of $50$ emu/g in the basal plane at $4.2$ K and a Néel temperature of $53$ K.