She has nearly black eyes and wears her iron gray hair in a bun. (NS,Ch17) Her iron gray hair is worn in a bun with many gold ornaments. (ACoS,Ch18) She is 5'5" and handsome with a fair complexion. (Robert Jordan's notes)
See Cadsuane's chapter points of view.
The following is an excerpt from Robert Jordan's notes on Cadsuane. It was published for The Great Hunt, part of the publicity for the release and signing tour for Brandon Sanderson's 'The Alloy of Law' in November 2011.
Cadsuane Melaidhrin was born in 705 NE in the city-state of Far Madding. At the age of fifteen, she went to the White Tower. There she spent six years as a novice and five years as Accepted. She might have moved faster as novice and Accepted - in fact almost certainly should have - but she was noted for both her stubbornness and her pride (read arrogance). At age 26, she was raised Aes Sedai and chose the Green Ajah.
Cadsuane was very strong in the One Power; for many years she served as the gauge by which every incoming novice was judged. In the last thousand years, no one had matched her and few had come close. Certainly no one in that time had exceeded her. Not even with her full strength yet, she was, on the very day she attained the shawl, at the pinnacle of the Aes Sedai social hierarchy.
She stood about 5'5" tall and was neither slender nor stout. She was not pretty, but she was strikingly handsome with a fair complexion. She had dark eyes, which some people occasionally mistook for black, especially when she was focused on them in an unpleasant fashion. Her hair became iron-gray, and she wore it in a bun on top of her head; the bun was decorated with small dangling golden ornaments, stars and moons and birds and fish. These hair ornaments were considered something of a trademark because she had worn them for as long as anyone could remember. For many sisters, the fact that she had was just one more indication of how set in her ways she was; they thought Cadsuane would never change, could never change. Of course, this was far from true; Cadsuane was remarkably adaptable, as befits someone who survived as long as she.
Cadsuane was considered by many to be a second Caraighan Maconar, although unlike Caraighan Maconar, she always refused offices. She preferred the field, so to speak; adventures were her bag. It was said that Cadsuane went through more Warders than most sisters have shoes; she didn't have all that many, since she was as vulnerable to the effects of a Warder's death as anyone else. Later in life, she refused to take another Warder because she felt that at her age, bonding a Warder would not be fair to the man.
Cadsuane first refused to be raised a Sitter in 846 NE; she reportedly did so a second time as well, though even on refusal was unheard of. She refused to be raised head of the Green Ajah in 862 NE, another thing that was unheard of. She was said to have vanished from the Tower for ten years (from roughly 890 NE to 900 NE) when she learned that the Hall intended to raise her Amyrlin after Sereille Bagand. She retired to northern Ghealdan about twenty-five years before the Aiel War, but came out of retirement, with her two surviving Warders, for that conflict. Soon after the Aiel War ended, she returned to her rustication. She claimed to have been raising roses when Logain appeared. His appearance drew her out of retirement again, but she was not interested in escorting him to Tar Valon and decided to wander a bit. Then Mazrim Taim rose up, and she headed for Saldaea as fast as she could ride.
When Siuan Sanche and Moiraine Damodred had reason to research Cadsuane because of their encounter with her shortly after reaching the shawl, they found many stories regarding Cadsuane. All of the ones that they were able to trace down turned out to be true, but in some cases the truth was more than the story. They were not able to follow or confirm all of the stories, of course.
One of the most prevalent Cadsuane stories was that she had once physically assaulted an Amyrlin Seat. Since physically assaulting any sister is a serious offense - and an Amyrlin even more so - the fact that Cadsuane apparently escaped any punishment at all, and that the tale is vague about which Amyrlin it was supposed to be, made most everyone think this story was false. It wasn't; it was the method Cadsuane used to turn Myriam Copan from a weak Amyrlin to a strong one in 758 NE. Myriam was thought to have gone on a two-month retreat by herself, but she had, in fact, been all but kidnaped by Cadsuane. Turning Myriam around involved, among other things, turning her upside down at least once. Although Myriam certainly had reason to keep the events of those two months secret (she was able to make a statement which seemed to deny that Cadsuane had assaulted her), it is the basis of the tale that Cadsuane once physically assaulted an Amyrlin.
Another story said that long ago she had removed a sitting king from his palace and taken him to Tar Valon to be gentled. In truth, Cadsuane had -a nose- for men who can channel. She faced more of them than any other sister living; she herself said more than any two Reds, maybe more than any ten. This seems to indicate at least twenty of them in that time, maybe more. She brought more of them to Tar Valon than any other sister. Of these, she never had to kill one, either because she could not capture him or because he was trying to escape. These men have ranged over the years from farmboys to nobles to the king of Tarabon, but one and all, they made much better adjustments to their fate than is considered normal. They eventually died short of a normal span, but they lived considerably longer than usual. For that King of Tarabon: he had to be winkled out of his palace, avoiding his army, which sought to rescue him. She carried him all the way to Tar Valon for gentling by herself, though pursued by his army that refused to believe that he was what he was.
It was also said that she kidnaped a King of Arad Doman and a Queen of Saldaea. After she released them, a war that had seemed inevitable simply faded away. She did actually spank or switch three reigning kings and four queens, though the facts of these are hidden in rumor.
Cadsuane is alleged to have once single-handedly stopped a coup in the White Tower. That did happen, though no one seems to know or agree on when. The true story: Cadsuane and Sereille Bagand did not get on with each other. In fact, they could not stand one another. Each was the sort of woman who dominated a room - or for that matter, a city! - by simply entering, and they struck sparks at every meeting. Despite her dislike for Sereille, though, Cadsuane uncovered a plot to overthrow Sereille and crushed it. The plotters thought she would be eager to join them, but she dragged the weeping ringleaders to Sereille and made them throw themselves on Sereille's rather small mercies. Sereille was not particularly pleased to have been saved - the plot was well laid out and ready to leap off - by one she so disliked.
She had a reputation for standing White Tower custom on its head, twisting it as she chose, and even violating it outright, as in her frank speech about age, her direct questions and refusals to accept oblique answers, and her interference in the actions of other sisters. The same could be said of her regarding Tower law, for that matter. She had a reputation for taking direct action, even to the point of violence, slapping faces, boxing ears, and more (especially when faced with what she considered stupidity), with high as often as low, or rather, more often. She also had a reputation for not caring whether she dented somebody's pride, if she thought it necessary.
There are the usual tales expected of a Green, only more of them. Riots suppressed and wars stopped single-handedly; rulers steadied on their thrones, or pulled from them, sometimes toppled openly and sometimes more subtly (toppling rulers was something Aes Sedai had not really done much of in the last thousand years, but Cadsuane seemed in many ways a throwback). Rescuing people carried into the Blight or kidnaped by dangerous bands of Darkfriends, breaking up murderous rings of Darkfriends plaguing villages and towns, and exposing of powerful Darkfriends who tried to kill her to protect themselves. There are dozens, even hundreds, of improbable and sometimes seemingly impossible tales.
Some of these are not so much tales about her as an impression, a belief: Cadsuane will do what she intends to do, and no one can stop her: not a king or a queen, not an Amyrlin - not even the Dark One himself, some claimed. And when Rand al'Thor arose to power as the Dragon Reborn, Cadsuane once again chose to take part in directing the events of the world.