RE:RE:MetricsClara is 100% owned by Lucara so there will have to be some internal arrangement about how the accounting works for Karowe stones. The price to the customer will have been agreed online and the Bots govt royalty will be 10% of that (to be paid by Lucara). In the case of Botswana, stones for export will also attract 10% export tax which is payable by the exporter (buyer).
Just how much will accrue to Clara vs Lucara from Karowe stone sales has not been revealed yet. It matters because there is a management rake-off from Clara's EBITDA.
We assume that the savings from eliminating middlemen more than covers this and is still a plus for Lucara.
When it comes to stones sold on behalf of other producers it will be a different story; probably a % commission? The producer concerned will be responsible for any royalties due any govt involved. Similarly the buyer will be responsible for any export taxes.