Bronze brass copper manhole well covers

The manhole covers can be made to look like bronze, brass, or copper, using four methods to decorate the copper surface of cast iron:
1. Casting bronze or copper requires a lot of copper, which is expensive, but it is suitable for long-term use;
2. Using cast iron as the load-bearing foundation and placing a 8mm thick relief copper plate in the recessed grooves, suitable for long-term use;
3. Using cast iron to cast patterns and text, and then laser-coating a 0.5-1mm thick bronze, brass, or copper layer on the surface to reduce production costs. It can be used for 6-8 years without wear, even if it wears out, it will still look good, suitable for long-term use;
4. Using cast iron to cast patterns and text, and then electroplating a 0.1mm thick bronze, brass, or copper layer on the surface to reduce production costs. It can be used for 1 year before wear, but it is very cheap and not suitable for long-term use.