This city has a special relationship to trade. With trade comes raw materials for decorative purposes and local fare; these often interact with local environmental factors, and the presence of natural material like juniper can affect the colors of the cityscape; copper ores and red ochre stones are also scattered through the city in unexpected ways. These influences can form a pleasing juxtaposition, like a Metaline collage of the cityscape painted red with copper ochre. A mixture of copper with calcium from groundwater to make pigments can produce yellows and sometimes reds; juniper berries are often grown in city gardens for the brilliant red color; and jadeite stones can be found sprinkled on the beds of lakes and in streams and riverbeds. These natural materials are combined in charming ways on the facades of the city and in the ornamental patterns of roofs and cornices. Additionally, the local terra cotta roofing tiles are sometimes stamped with certain designs; to achieve a similar effect, the sunlight streaming in over stone walls or through leafy trees would create a fanciful mosaic of colors and swirls in the sky over the roofs. In the city, the rivers bend to create grooves and scallops of different colors in both banks; these rocks are laid into the riverbeds for people to walk on when crossing the river in order to protect their feet from rocks and debris. Despite their neglect, the city streets and buildings remain intact and interesting to this day. These stones were often shaped and carved by the local inhabitants as a means of decoration and to beautify their homes and workspaces.