Quartz has been synthesized under hydrothermal conditions at rates of 1.78 mm/day in the presence of LiNO2 in Ag lined and Ag plated systems, and it is shown that such quartz has optical transmission between 1500 Å and 3 µ equal, and in some cases superior to, natural quartz. The uv cutoff at about 1500 Å has been shown to be associated with Fe whose concentration may be reduced by procedures that reduce the concentration of charge compensating H+ in the lattice (growth in LiNO2) and by procedures which reduce the concentration of Fe in solutions (inert conditions). Transmission near 3 µ is affected by OH which can be reduced by LiNO2.
A. A. Ballman, D. M. Dodd, N. A. Kuebler, R. A. Laudise, D. L. Wood, and D. W. Rudd, "Synthetic Quartz with High Ultraviolet Transmission," Appl. Opt. 7, 1387-1390 (1968)