Natasha Denona Golden Aquamarine (86P) is a warm aqua with a frost finish that is permanent in palette and retails for $29.00. In comparison, Lethal Cosmetics Sigil is a cool aqua with a metallic finish that is permanent and retails for $6.50.
Lethal Cosmetics Sigil is 85% similar — it is more shimmery, lighter, cooler.