Slate Fire is a color shifting shimmer nail polish, and is opaque in approximately two to three coats.  It is a saturated dusty blue base with shimmer that shifts from red to gold to green, and flashes vivid red and bright green at the extremes of its color range.  The shimmer pigment is commonly known as unicorn pee, and is the same pigment used in the Phoenix-type polishes of Starlight Polish's Mythological line.

This polish is part of the By Request collection, a set of six polishes originally commissioned as customs by one very generous lady, who agreed to allow them to be added to the Starlight Polish line so everyone could enjoy them! 

The last photo shows what Starlight Polish 15mL and 7.5mL bottles look like.

This polish contains "unicorn pee" pigment. The red to green color shifting pigment in this polish is the same kind of pigment that's in the original elusive unicorn pee polishes (Clarins 230, Liquid Euphoria Bliss, etc).