What are granny's chips diamonds?

One familiar use of the term 'Granny's Chips' comes from the British Royal family, and is used as a descriptor for the chips removed from the 3,000+ carat Cullinan Diamond when it was being cut and faceted as a major gemstone for the British Crown Jewels. Granny in this case is Queen Mary, wife of Edward VII who received the uncut Culllinan as a gift from the mine's owner.

You can see these 'chips' in the links, below.