Portu-sand, inc. Is a us-based company dedicated to the worldwide exportation of silica sand from guyana in south america rated among the best and of the highest quality in the western hemisphere and certified for the specific use of glass manufacturing, golf course, beach filling, construction and plastering. Comparative sand analysis Chemical analysis Sio2 99.700% - 98.5% minimum Fe2o3 0.083% - 0.060% Max 0.055% Al2o3 - 0.017% - 0.070% Max 0.35% Cao 0.084% Max 0.20% Tio2 0.012% Max 0.05% Mgo 0.125% Max 0.20% K2o 0.063% Na2o 0.038%