My favourite Mica Powder are Cosmic Shimmer Pixie Powder ( SBC | JGG ) and Cosmic Shimmer Pixie Sparkles ( SBC | JGG ) Both for the wonderful range of colours, you can choose from and for availability.
Another Brand I like but is a bit harder to come by are Nuvo Shimmer Powders ( SBC | SSS ) There are also fewer colours to choose from.
And one of the powders that have been along for quite some time are Lindys Magicals ( SBC | SSS ) Another good quality Mica Powder that comes in a jar instead of a bottle. I am familiar with their powders as they are also used for the famous Lindy’s Sprays. The Lindy’s Sprays come in a spray bottle with the mica powder and you need to add water yourself.