Gem Diamonds’ revenue rose in the first quarter as demand for rough from its Letšeng mine in Lesotho began to return. Sales grew 17% year on year to $43 million for the three months ending March 31, the company said last week. Sales volume climbed 27% to 32,571 carats, outweighing an 8% drop in the average price to $1,321 per carat. The result reflected a favorable comparison with the same period in 2023 when rough