This work discuss the development of magnetic glass-ceramics based on reused laboratory borosilicate glassware and iron-rich scale (a by-product from metallurgical industry). Raw materials were initially milled and characterized, different compositions were established with increasing contents of scale (20, 30, 45 wt.%) in the samples.The three selected compositions were melted (1550 °C/4h) and later cast in a preheated steel mold at 400 °C. Then, samples were annealed at 700 ºC/30 min. The obtained glass-ceramics were investigated by X-ray diffraction (DRX), vibrating-sample magnetometer (VSM), scanning electron microscopy (SEM). Magnetite crystals in the glass-ceramics were evidenced by SEM images. VSM analysis revealed that the obtained ferrimagnetic glass–ceramic in the composition with 45% of scale improved the magnetization saturation (Ms), reaching 28,5 emu/g. Results indicate a great potential for these magnetic glass-ceramics for some applications, such as in magnetic hyperthermia, waste sorbent and microwave absorption devices.