The emeralds were mined within an area of 70 square miles, comprising
at least nine separate communities collectively called by the ancient
Romans "Smaragdus Mons" (indicated in blue on the map). Except for the
settlement of Nugrus, which also possess some well-preserved buildings,
none of the other mining sites is of the same magnitude of importance
as the town of Sikait.
All along the hillsides of the wadi Sikait one finds the entrances to
the ancient mine shafts. The first mines may have been opened in the
Ptolemaic period, but the heyday of emerald mining was certainly in
Roman times with many mining centres simultaneously active. After the
Muslim conquest of Egypt in 641 AD the emerald mining continued, although
with interruptions and on a smaller scale, well into the 14th century
AD. The remaining mining activities then rapidly declined, as imports
of emeralds from India and especially higher-grade stones from Columbia,
after the Spanish conquest of much of South America, became more common.