In the community of Nigua, Province of San Cristobal, Dominican Republic, are the open pit quarries that produce must of the sand consume to make concrete blocks, or as it is call "the sand of the poor"; meaning that that are use by lower income people for their buildings and house's construction. The "Mine of the Coronel" as it is call due to its previous owner, it is one the oldest. This is a documentary of the daily life of workers. Where days are long, start at 6:00 AM and finish around 8:00 PM, thus the name of being within and hourglass full of sand.