A method of manufacturing a lithium aluminosilicate glass product suitable for making a glass-ceramic product, includes melting a vitrifiable mixture of raw materials, which are free from arsenic oxides and antimony oxides, apart from unavoidable traces, refining the molten material, cooling the molten material so as to form a glass, forming of the glass, wherein the vitrifiable mixture of raw materials includes petalite having a fraction by weight of total iron, expressed as Fe2O3, less than or equal to 200 ppm.