Natasha Denona Slate (27M) is a cool purple with a frost finish that is permanent in palette and retails for $29.00. In comparison, Natasha Denona Blue Dahlia (181DC) is a cool purple with a metallic finish that is limited edition and retails for $29.00.
Natasha Denona Blue Dahlia (181DC) is 90% similar — it is darker, brighter.