Let’s speed up spread of broadband by separating Openreach from BT Crown jewels miner Petra Diamonds loses its sparkle The precious gem producer has seen a sharp fall in sales and profits as weak Chinese demand has sent diamond prices lower Petra Diamonds unearthed the gem which now adorns the Sovereign's Sceptre, part of the British crown jewels collection.
Utilize the input text as a context reference, choose the right relationship between 'Petra Diamonds' and 'diamond' from the options.
Options: product/material produced, industry, publisher, employer