It takes billions of years for a single diamond to form. Over this time, tiny pinpoint marks known as inclusions can form inside the structure. This is natural in the formation of a crystal and part of what makes each diamond unique. Inclusions are so small that the stone must be magnified with a 10x lens to find them.

The term ‘internally flawless' is applied only to the very rare examples that possess no inclusions. Asprey sells only diamonds of clarity VS2 or above i.e. with very small inclusions.