PRAIA, July 18 — On a rocky Cape Verde beach, Maria and Vania fill their buckets with black sand the moment that waves recede, transporting it on their heads to a stockpile where...

On a rocky Cape Verde beach, Maria and Vania fill their buckets with black sand the moment that waves recede, transporting it on their heads to a stockpile where it will be sold…

PRAIA, July 18 — On a rocky Cape Verde beach, Maria and Vania fill their buckets with black sand the moment that waves recede, transporting it on their heads to a stockpile…