Medical Au-Pt-Pd alloy

A medical Au—Pt—Pd alloy comprising Au, Pt, Pd, and inevitable impurities, wherein

• the medical Au—Pt—Pd alloy has an alloy composition inside a polygon (A1-A2-A3-A4-A5-A6) surrounded by straight lines connected at point A1 (Au:
• 37.9 atom %, Pt:
• 0.1 atom %, and Pd:
• 62 atom %), point A2 (Au:
• 79.9 atom %, Pt:
• 0.1 atom %, and Pd:
• 20 atom %), point A3 (Au:
• 79.9 atom %, Pt:
• 20 atom %, and Pd:
• 0.1 atom %), point A4 (Au:
• 69.9 atom %, Pt:
• 30 atom %, and Pd:
• 0.1 atom %), point A5 (Au:
• 49 atom %, Pt:
• 30 atom %, and Pd:
• 21 atom %), and point A6 (Au:
• 39 atom %, Pt:
• 40 atom %, and Pt:
• 21 atom %) in a Au—Pt—Pd ternary state diagram, and
• in a metal structure on any cross-section,
• with a composition of a mother phase Au—Pt—Pd alloy as a criterion, a total of an area ratio of a Au-rich phase which is an alloy phase having a Au content higher by 4 atom % or more than that of the mother phase and an area ratio of a Pt-rich phase which is an alloy phase having a Pt content higher by 4 atom % or more than that of the mother phase is 1.4% or less.