Neodymium is a rare earth metal and a special material: in combination with iron and boron (Nd2Fe14B), it can be used to produce the world's strongest permanent magnets.
The majority of NdFeB magnets are currently produced in China. The reason for this is that 97% of one of the raw materials, neodymium, is mined and extracted in China.
The magnets have a nickel-copper-nickel coating. This gives them an attractive silver surface.
Available here as a pack of 8 with many different depths.
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