Sydney Grace Shaley's Shimmer (Unbreakable Bond) is a cool gray with a metallic finish that is permanent in palette and retails for $6.25. In comparison, Natasha Denona Chromatic (04M) is a cool silver with a metallic finish that is permanent in palette and retails for $29.00.
Natasha Denona Chromatic (04M) is 90% similar — it is more shimmery.