It's called the Lares Tiara, and it is made by TheWaughdrobe on Etsy.
Also, she has this beautiful Florae Necklace, Bracelet, and Earrings set, which is very gorgeous!
My favorite, however, are these absolutely stunning earrings! They are called A Kiss From a Rose, and they are so lovely and elegant.
You can find lots more where these came from! Visit TheWaughDrobe on Etsy to see more.