The present study addresses an innovative methodology for the design and creation of mineral-impregnated fiber-reinforcement structures utilizing magnesium oxychloride (MOC) cement and commercial alkaline-resistant glass fiber (AR-GF) rovings. The approach of custom-built material design and manufacturing equipment makes a high-quality and stable impregnation process possible, ensuring efficient industrial manufacturing and great flexibility in field applications. Particular fresh mineral-impregnated glass fibers (MGFs) are air-cured at ambient temperature and evaluated over the course of 28 days. The MGF composites exhibit a considerable initial strength after the 1st day, with further improvement with subsequent curing periods, particularly until the first 7 days. The remarkable flexural and tensile performance achieved by the MGF prototypes at both 1-day and 28-day curing periods is in the same range as currently available fiber-reinforced polymers (FRP). Analysis using mercury intrusion porosimetry (MIP), environmental scanning electron microscope (ESEM) and micro-computed tomography (μCT) validate a more reacted and densified matrix microstructure and enhanced fiber-matrix interphase due to prolonged curing. The proposed reinforcement type leverages a sustainable impregnation medium and digital production, contributing to carbon-neutral, lightweight and fire-safe construction.