I wish there was a photo of Ella in the set. With her lovely coloring it must've been lovely. Queen Marie of Romania, when she writes about Ella in an aquamarine gown:
'...Tall, slim, graceful and infinitely gracious, a vision, a joy for the eyes, for the soul, for the heart.... Her cacoshnic of emeralds and diamonds is truly a halo to her angelic face, and the gorgeous gems covering arms and throat have...the aspect of gifts piously offered to some beloved saint. Tall, slim, graceful and infinitely gracious, a vision, a joy for the eyes, for the soul, for the heart. Yes, a vision! One feels like kneeling down when she passes in the hope of being able to touch, if only for a second, the hem of her gown... the vision of you passing before me like a blessed apparition in your gown the colour of glaciers, color of aquamarine....'
Aquamarine's would've particularly suited her, I think, based on the descriptions of her delicate 'fairy-like' beauty. They seem so pure and clear. Other jewels may have been too 'heavy' for her--semi-precious stones I think would've been best. (Though we all know of her beautiful emerald collection.)