Button styles and classifications

Button materials are roughly divided into plastic (resin, plastic), metal buttons (copper, iron, alloy), natural (shell, wood, coconut shell, bamboo)
Various materials are used to make buttons, and the process is different. Some buttons look the same, even people in the industry can't tell them apart with their eyes, so they can only be distinguished by scratching off the coat if they are damaged.
For example, plastic and resin buttons, plastic (including all kinds of plastic) buttons are generally die-cast, so there will be a line on the side of the button, this parting line, some factories may remove this line in subsequent processing , but his weight is lighter than resin (some plastics will be heavier).
The resin buttons are mechanically carved and then polished, so the surface has no full mold lines and is very smooth. But it is fragile, the surface is easily scratched, and it will become soft when placed in boiling water.
The other is the button made of copper and iron, which can be known by trying it with a magnet. There is also a hard object to scrape off the surface plating layer, and the brass (golden) color in the copper button surface. The iron buckle is black, which is the color of the raw material.
The alloy buckle is relatively heavy and is made of die-casting. All mold lines are generally ground and polished. You may not see it, but it is very heavy and solid.
There are many styles of buttons, including four holes, two holes and one hole on the back.