This Fairy Stone is from Hurricane River, Quebec, Canada. This piece measures approx. 64 x 57 mm: thickness is approx. 11 mm: weight is 65 grams.
 
Fairy Stones are a mixture of Calcium Carbonate and Clay. They tend to form in disc shape. They are also known as Melinite Opal or Goddess Stone. They have a MOHS of 5 and can be found in US, Canada, Greenland, UK and Morocco.