From A Wiki of Ice and Fire
Dawn is the ancestral greatsword of House Dayne, whose wielder is always given the title Sword of the Morning. Dawn is largely the reason for House Dayne's fame. Its origins are lost to legend, but it seems likely that the Daynes have carried it for thousands of years. It is said to be made from metal forged from the heart of a fallen star. The blade is as pale as milkglass, looking like no Valyrian blade, yet sharing all of the properties, being incredibly strong and sharp. Unlike other houses who have ancestral swords, House Dayne does not pass its sword from lord to lord. Only a knight of House Dayne who is worthy can wield it. The name of the Daynes' castle, Starfall, and their arms, featuring a white sword and falling star, both reference Dawn.
|“||Dawn remains at Starfall, until another Sword of the Morning shall arise.||”|