ColourPop On a Lark is a cool fuchsia with a semi-matte finish that is limited edition and retails for $4.50. In comparison, ColourPop Pillow Mint is a warm pink with a matte finish that is limited edition and retails for $4.50.
ColourPop Pillow Mint is 90% similar — it is less shimmery, lighter, brighter, warmer.