The ingot is usually seen in metal place because it is a block or some other shape that is made of metal and shaped into an object. Stringers are known as the fine lines that are likely to occur in groups caused by non-metallic impurities. These are present in the original metal and extruded lengthwise. Often, manufacturing companies will have factories to make different items out of metal.
These metals are melted down into a liquid and then it is shaped usually into a mold so that it will harden into the correct shape. However, sometimes impurities happen during this process. A line may form in the metal as it is hardening. Also, dust or dirt may accidentally fall into the liquid metal while it is hardening.