METHOD OF PRODUCING GLASS WITH ALEXANDRITE EFFECT Russian patent published in 2025 - IPC C03C3/68 B44C5/08 C03C4/02 

FIELD: glass.

SUBSTANCE: invention relates to production of coloured glass having an alexandrite effect based on a low-melting matrix, which can be used in making articles for jewellery and decorative and art purposes. Glass with alexandrite effect is obtained from a mixture of reagents of silicon, germanium, boron and calcium oxides, which form low-melting borosilicate glass, at a ratio of, wt.%: SiO₂=25-35, GeO₂=10-20, B₂O₃=35-45, CaO=10-20, and additionally two oxides of rare-earth elements, such as Pr and Nd, or Pr and Ho, or Nd and Ho, or Sm and Ho, taken in stoichiometric ratio of 1:1 in amount of 10% by weight of total glass components. Charge is heat treated at temperature of 800 °C, homogenisation, preparation of the melt by heating charge to 1,000-1,050 °C is held during a day in a platinum crucible, after which it is quickly cooled to room temperature by pouring the melt from the platinum crucible into a glass-graphite crucible.

EFFECT: obtaining glass with alexandrite effect.

1 cl, 1 ex, 3 dwg