The search for new crystalline host materials for the usage in lasers emitting in the eye-safe spectral range of 1.5–1.6 μm is an important task. The aim of this work was to study the growth technique, spectroscopic properties and laser characteristics of new active media – crystals Er3+,Yb3+:Ca3RE2(BO3)4 (RE=Y, Gd). Calcium-yttrium Er3+,Yb3+:Ca3Y2(BO3)4 (CYB) and calcium-gadolinium ...