She is tall with a square face and steel gray hair in braids to her waist. (NS,Ch12)
Chronology
Learning of Siuan's skill at puzzles, Cetalia Delarme conscripts her as her assistant as the Blue Ajah eyes-and-ears head. (NS,Ch12)
Cetalia works Siuan hard at analyzing reports. (NS,Ch14)
Other References
NS,Ch14 – Siuan quickly becomes frustrated at her lack of free time because of Cetalia's demands, Cetalia is currently stronger so she has no choice.
NS,Ch18 – It will be three or four years before Siuan is strong enough to quit her job with Cetalia. Knowing this, when Moiraine sees Siuan she thinks that Sierin Vayu discovered their plan and sent Siuan to bring her back.
Books 