Chameleon rose
From Memory Alpha, the free Star Trek reference
A chameleon rose is a flower that changes color with the mood of its owner.
In 2364, Wyatt Miller gave Deanna Troi a chameleon rose as a gift. The rose had golden leaves and a golden stem. It was blue when Miller held it and turned red, then white when Troi held it. It later turned purple while still in Troi's hands. (TNG: "Haven")
Though Troi's mood changed once her mother arrived, the rose remained white.
