Diamond-rich Botswana expects mineral revenues in the 2019/20 fiscal year to drop by 4% to 13.6-billion pula ($1.26-billion) due to a decline in royalties and dividends, a minerals ministry budget document showed on Thursday. Mineral Resources Minister Eric Molale said in the document that global diamond demand was showing signs of slowing down. Retail jewellery sales fell during the last quarter of 2018, he said, while polished prices continued to decline into the beginning of 2019, albeit at a slower rate.