Tanto quanto me lembro, eles são muito mais poderosos. Mas tem sido anos desde que eu li qualquer um deles. (Eu fiquei esperando a série terminar ... Então ele morreu .. então .. gah!)
A partir da WOT Wiki em Angreal :
Sa'angreal are like angreal, but much more powerful. All known angreal and sa'angreal are aligned for use by either a man or a woman, never both.
Veja também: Sa'angreal
are similar to angreal in that they allow channelers to use more of the One Power than they could otherwise safely access. Lots more. All sa'angreal multiply exponentially the amount of the Power upon which the channeler may draw; probably as a consequence, they are much rarer even than ordinary angreal.
Algumas passagens relevantes dos livros sobre eles ... (tentando encontrar tanta descrição do que são / de onde vieram / etc.)
A Grande Caçada:
That girl had remembered tales of angreal and even more powerful sa'angreal – those fabled remnants of the Age of Legends that allowed Aes Sedai to channel more of the One Power than any could safely handle unaided – remembered and thought some such focus was required to channel at all.
"Ter'angreal do many things, child. Like angreal and sa'angreal, they are remnants of the Age of Legends that use the One Power, though they are not quite so rare as the other two. While some ter'angreal must be made to work by Aes Sedai, as this one must, others will do what they do simply with the presence of any woman who can channel. There are even supposed to be some that will function for anyone at all. Unlike angreal and sa'angreal, they were made to do specific things.
"What is it?" Rand asked.
"A sa'angreal." She sounded as if it were really not very important, but Perrin suddenly had the feeling the two of them had entered a private conversation, saying things no one else could hear. "One of a pair, the two largest ever made, that we know of. And an odd pair, as well. [...] Together, they might well be powerful enough to Break the World again, perhaps even worse than the first Breaking."
O dragão renascido:
Sa'angreal were like angreal, allowing an Aes Sedai to channel more of the Power than she safely could unaided, but far more powerful than angreal, and rare.
Sa'angreal had no power of their own, of course – they were merely devices for focusing and magnifying what an Aes Sedai could channel – but with that wand, a strong Aes Sedai might be able to crumple the walls of Tar Valon.
A Grande Caçada:
With one of the even rarer sa'angreal, the flows could be increased as much over those possible with an angreal as an angreal increased them over channeling naked.
Os fogos do céu:
"If I can make this one, I can make others. Maybe I can even make angreal and sa'angreal. No one in the Tower has been able to do that in thousands of years!"