Brass manhole covers

Copper-finished manhole covers.
They can be made to look like bronze, brass or red copper, and there are four methods to create copper-surfaced manhole covers:
1. Casting bronze or red copper, which requires a large amount of copper and is relatively expensive, but suitable for long-term use;
2. Using cast iron as the load-bearing base and placing an 8-millimeter-thick embossed copper plate in the surface grooves. The two materials are physically combined to form a complete finished manhole cover. This method is suitable for small batches and can be used for a long time;
3. Casting patterns and characters with cast iron and then laser-coating a 0.5 – 1-millimeter-thick layer of bronze, brass or red copper on the surface to reduce production costs. It can be used for 6-8 years without wearing out, and even if it does wear out, it still looks good, making it suitable for long-term use;
4. Casting patterns and characters with cast iron and then electroplating a 0.1-millimeter-thick layer of bronze, brass or red copper on the surface to reduce production costs. It can be used for one year before wearing out, but it is very cheap and not suitable for long-term use.