Giorgio Armani Spring-Summer '17 is a cool blue with a pearl finish that is limited edition and retails for $39.00. In comparison, Natasha Denona Electrick (364M) is a cool blue with a metallic finish that is limited edition and retails for $29.00.
Natasha Denona Electrick (364M) is 90% similar — it is more shimmery, lighter, cooler.