A lovely pottery 'Plate' from the rare series of twelve 'Spirit of the Flowers' - 'Violet'.
Possibly used for a scale?
By Mintons, pattern No. 1347 attributed to John Moyr Smith, a lovely piece of aesthetic movement design. 
Impressed 'MINTONS' mark underneath, image 8
 
Violet spelt out in each corner-
Image 4  'VI', image 5 'OL', image 6 'E', image 7 'T'
 
The series consists of-
LILY OF THE VALLEY
DAISY
FOXGLOVE
ANEMONE
POPPY
WATER LILY
VIOLET
SNOWDROP
WILD ROSE
CONVOLVULUS
PRIMROSE
LILY
 
In lovely condition, very feint staining at the back
 
Dimensions: Diameter 21cm, thickness 1cm