A seal assembly for limiting gas leakage between a hot gas path and a cavity containing cooling air in a turbine engine, the seal assembly comprising: a first blade assembly comprising a first platform and a first airfoil, said first platform comprising a first mate face; a second blade assembly comprising a second platform and a second airfoil, said second platform comprising a second mate face located in opposing facing relationship with said first mate face; a first seal slot formed in said first mate face and extending into said first platform in a circumferential direction (D ROT) of the engine, wherein said first seal slot is defined by opposing radially inner and radially outer first walls (40, 42) of said first seal slot and by opposing second walls (44, 46) of said first seal slot extending between said first walls (40, 42), wherein said first seal slot defines an elongated dimension extending across said first mate face from said radially inner first wall to said radially outer first wall, and said elongated dimension angles axially from an outer axial side of said first platform toward a central portion of said first platform, extending outwardly in the radial direction; a first seal member slidably disposed in said first seal slot and including a circumferentially facing contact surface; characterized in that at least the radially outer one of said first walls (40, 42) is angled relative to a line perpendicular to said first mate face such that an entry portion of said first seal slot located at said first mate face has a larger width than a circumferentially inner end portion of said first seal slot; and wherein rotation of the seal assembly during operation of the engine causes an exertion of a centrifugal force on said first seal member in the radial direction so as to cause said first seal member to slide circumferentially partially out of said first seal slot to engage said contact surface into contact with said second mate face. a first blade assembly comprising a first platform and a first airfoil, said first platform comprising a first mate face; a second blade assembly comprising a second platform and a second airfoil, said second platform comprising a second mate face located in opposing facing relationship with said first mate face; a first seal slot formed in said first mate face and extending into said first platform in a circumferential direction (D ROT) of the engine, wherein said first seal slot is defined by opposing radially inner and radially outer first walls (40, 42) of said first seal slot and by opposing second walls (44, 46) of said first seal slot extending between said first walls (40, 42), wherein said first seal slot defines an elongated dimension extending across said first mate face from said radially inner first wall to said radially outer first wall, and said elongated dimension angles axially from an outer axial side of said first platform toward a central portion of said first platform, extending outwardly in the radial direction; a first seal member slidably disposed in said first seal slot and including a circumferentially facing contact surface; characterized in that at least the radially outer one of said first walls (40, 42) is angled relative to a line perpendicular to said first mate face such that an entry portion of said first seal slot located at said first mate face has a larger width than a circumferentially inner end portion of said first seal slot; and wherein rotation of the seal assembly during operation of the engine causes an exertion of a centrifugal force on said first seal member in the radial direction so as to cause said first seal member to slide circumferentially partially out of said first seal slot to engage said contact surface into contact with said second mate face.