Pat McGrath Astral Lilac Aura is a cool lavender with a sparkle finish that is permanent in palette and retails for $25.00. In comparison, Natasha Denona Illusion (423DC) is a cool duochrome with a pearl finish that is limited edition and retails for $29.00.
Natasha Denona Illusion (423DC) is 80% similar — it is less shimmery, lighter, cooler.