With regard to your first question, I was wondering the same too. Found this Coindesk article which might be helpful (https://www.coindesk.com/everledger-blockc

With regard to your first question, I was wondering the same too. Found this Coindesk article which might be helpful (https://www.coindesk.com/everledger-blockchain-tech-fight-diamond-theft/ https://www.coindesk.com/everledger-blockchain-tech-fight-di...). "Before a stone like this can be digitised, pricey or not, it needs a unique identifier – a fingerprint – that allows it to be tracked on Everledger’s platform as it changes hands. This is calculated from 40 data points related to each stone – alongside the Four C's. Any diamond over 0.16 carats will also have a serial number inscribed on its girdle during the grading process. While a criminal could reshape a stone to distort its 'digital fingerprint', Kemp explained that diamonds are not, in fact, the sum of their parts. The cutting process results in a lot of wastage, so any attempt to alter a diamond, or split it into two, will drastically reduce its value."