A hard precious metal alloy member is constituted of a gold alloy, which has a
gold Au content of from 37.50 to 98.45 wt %, and contains a hardening additive
in a range of not less than 50 ppm but less than 15,000 ppm, wherein the hardening
additive is constituted of gadolinium Gd only, or gadolinium Gd and at least one
element selected from the group consisting of rare-earth elements other than Gd,
alkaline-earth elements, silicon Si, aluminum Al, and boron B.
