These are small marks on an Amoux that may be any color found on any color swatch, including colors from Vibrant color swatches.

Any Amoux can have them regardless of the genotype, phenotype, or mutations. 

Do note that color modifying mutations such as Axanthic will still override the color of free markings.

 

These markings do allow for small elaborate/unusual shapes, as long as it doesn't look inorganic or resembles another marking the geno doesn't have.
Minimal markings may have up to two separate colors, but cannot have iridescence without the presence of Iridesence.

Minimal markings may also cover up to 50% of any of the following mutations:

Maned, Spiked, Paradise, Whiskers, Feathered coat feather crests