Calibration of the ruby pressure gauge to 800 kbar under quasi‐hydrostatic conditions

Abstract
An improved calibration curve of the pressure shift of the ruby R1 emission line was obtained under quasi‐hydrostatic conditions in the diamond‐window, high‐pressure cell to 800 kbar. Argon was the pressure‐transmitting medium. Metallic copper, as a standard, was studied in situ by X ray diffraction. The reference pressure was determined by calibration against known equations of state of the copper sample and by previously obtained data on silver.