They are termed as the Iron rugs of Iran, thanks to their durability and weight. They are also known for their pile thickness. Their two wefts are what made them heavy. They have high knot density to be piled thickly. Mina Khani and Herati are the most popular patterns in this category of oriental rugs. These hand-woven Persian rugs are made by Kurdish people in Iran in the town of Bidjar.