The Lily brooch is a female angreal in the shape of a flower similar to a lily but too-many-petaled. It seems to be carved from a stone.
It is considered weaker than average. If Cadsuane's weak Shrike angreal enables her to reach the strength of the top male level, it can be assumed that this brooch permitted Verin to reach almost the top female levels.
Verin had secretly kept the flower brooch for forty years. It is not known if she discovered it somewhere or if she snatched it from the White Tower angreal storeroom.
After the Sharans attack to the Aes Sedai camp in Kandor, Siuan Sanche is described using a flower brooch angreal very similar to the Verin's one. It can be either a completely different angreal or otherwise to be the same one, which somehow Verin, before her death, was able to leave in the White Tower or to send directly to Siuan along some of her mysterious letters.