Patent ID: 11987519

Abstract:
Glass ceramic material for the production of synthetic stones in fashion jewellery and jewellery, having excellent mechanical properties, chemical and heat resistance, harmless due to absence of lead, arsenic and cadmium compounds, available in a broad scale of colour designs, imitating faithfully natural precious stones thanks to high content of spinel crystalline phase and lowered content of SiO2, consisting of (in weight %):20-40% SiO2,1.5-10% B2O3,20-35% Al2O3,0.1-20% MgO,0.1-20% ZnO,the content of MgO+ZnO being at least 10%,preferably also0-15% TiO2,0.1-15% ZrO2,the content of TiO2+ZrO2 being at least 5%,more preferably also0-20% of colouring additives in the form of CoO, NiO, CuO, Fe2O3, MnO2, Cr2O3, V2O5, Pr2O3, CeO2, Nd2O3, Er2O3, AgO and Au.