If you see cocktail rings and dinner rings used interchangeably, that usage is correct. Both describe the same type of large, decorative ring built for social and formal occasions.
Stone Story
An ideal cut designation means the diamond was cut to proportions with a specific mathematical basis (Tolkowsky's 1919 calculations for table, crown, and pavilion angles that maximize the balance of brilliance, fire, and scintillation) a more precise starting point for evaluating light performance than cut grade ranges that cover a wider spread of proportions.
Origin Story
A Kashmir designation on a sapphire certificate is the trade's highest color credential: the deposit was active primarily in the 1880s through 1920s. The stones are now among the rarest in fine jewelry, and the velvety cornflower blue produced by fine silk inclusions remains the global benchmark against which all other sapphire color is assessed.