The price or value of diamonds is not controlled by any government on earth. The price of diamonds is controlled by markets.
Holland, Israel and India all include diamonds among their top exports and are included in the top countries exporting diamonds, by value..
Since this is an illegal activity, your answer depends on who holds the diamonds at the moment you ask the question.
You can call your local Value Village and ask if they have any diamonds for sale.
Diamonds are not generally wasted, given their monetary value and useful value as the hardest mineral known.
The best way to figure out the value of your diamonds is to visit a jewelry store and have them appraised by a professional. If you plan on selling your diamonds any local store that buys gold will probably buy diamonds as well and can give you a good resale value.
DeBeers
There are no diamonds mined in any European country.
White diamonds are valued on there color. The nearer a white diamond is to colorless the rarer it becomes. This raises the diamonds value. Imperfections in white diamonds lead to discoloring and can greatly reduce the value.
Every country uses diamonds, about 25% usually for jewelery and the remainder for industrial applications.
mINING
First, you should take your diamond to a trusted jeweler and have hem appraise your diamonds. Then you should get a Rapaport value which tells diamond values all over the country. Then you only need to find a buyer.
Diamonds are not sustainable, in the environmental sense.