摘要 |
<p>PURPOSE: To provide the method for coating a natural stone or synthetic stone capable of coating the natural stone or synthetic stone, and also capable of obtaining a hard coating. CONSTITUTION: At first, a palladium soln. is applied on a hematite series natural stone 21 to form a palladium layer 22. Then, nickel is plated on the hematite natural stone 21 by electroless plating to form a nickel layer 23 on the top surface of the palladium layer 22. Then, copper, nickel and 24-carat gold are plated in this order on the top surface of the nickel layer 23 by electroplating to form a copper layer 24, nickel layer 25 and gold layer 26, to obtain a coated matter 27. Then, the hematite series natural stone 21 of the coated matter 27 is magnetized to form a permanent magnet. The strength of magnetization is decided properly in accordance with application.</p> |