Natasha Denona Aurum is a warm gold with a metallic finish that is permanent in palette and retails for $29.00. In comparison, Natasha Denona Orium (251DC) is a warm gold with a metallic finish that is limited edition and retails for $29.00.
Natasha Denona Orium (251DC) is 80% similar — it is more shimmery, darker.