Some sapphires grow in the earth in such a way that when they are cut cabochon style (which is basically a smooth, domed shape), they display a six-rayed star that moves around as the stone is moved around a fixed light source. This is refered to as "asterism".
The Star of India, grayish blue, 563 cts.
The Star of Asia, blue, 330 carats.
The Stuart Sapphire, blue, 104 cts.
But not a person to be messed with because she will go all out to get back at someone.
James: Woah! She's a sapphire alright.
Everyone thinks Sabrina is a sapphire and so do i.
That girl sure is a sapphire, too bad she's taken.