The phrase "beautiful luster" means that something has a shiny and attractive appearance.
Sentences with «beautiful luster»
This pearl rope is the last of the pieces I borrowed from Lilia's Treasures Etsy shop (you can see the other pieces here and here), pink drops with beautiful luster. (theseventhsphinx.com)
Unlike painted toys, the stain does not chip - instead it maintains its beautiful luster and lasts for generations.) (blueberryforest.com)
This will keep your stone with a beautiful luster. (kellyscloset.com)