The code of trust

Trusting in Allah but treating man with greater caution was followed by the pearl fishers, both in their dealings with each other and with their captain. Whilst the oysters were being opened, four 'guards' or 'watchers', haras, from among the crew would sit inspecting the work to make sure no one who found a large pearl could hide it away to keep it for himself. ... There was no wage economy. This was their profit he would be stealing. ... The crew also had witnesses present when their captain was selling the pearls.... Nevertheless, they were aware ... that some captains secretly accepted presents from merchants.

Shaikhdoms of the Eastern Arabia, Peter Lienhardt, Palgrave.