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Name: Stephanie E.
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: Thursday, August 22, 2002


Question:
I thought that precious metals were not supposed to be magnetic (ie gold, silver and platinum). Yet I took what I thought to be a platinum engagement ring and held towards a magnet and it stuck. Does this mean that the metal is not pure? Or does it have something to do with the diamond?


Replies:
Regarding the ring, diamond is not magnetic or paramagnetic. The diamond could never stick to a magnet. The precious metals are also not magnetic, but they are soft and could not be fashioned into a ring unless other metals are used. Clearly your platinum ring has had ferrous material added to it. Ask the vendor, if the ring is platinum coated and/or which metals were used in making the ring.

Dr. Harold Myron


Platinum is actually paramagnetic. That means that it can become slightly magnetic in a magnetic field (such as near a permanent magnet), but its magnetism disappears when the magnetic field is removed. So, platinum will be weakly attracted to a magnet. Is this effect large enough to notice with a ring-sized hunk of platinum and an ordinary magnet? I do not know.

Diamonds, on the other hand, are diamagnetic, which means that they will NOT be attracted to a magnet. It is possible that the prongs on the ring that hold the diamond in place may be attracted to a magnet, but the diamond certainly will not be.

Richard E. Barrans Jr., Ph.D.
Director of Academic Programs
PG Research Foundation, Darien, Illinois


Stephanie, You are correct. The metals you mentioned are not attracted to a magnet. Likewise for the diamond -- also not attracted to a magnet. If your ring is attracted to a magnet it must contain iron, nickel, or cobalt somewhere in the metal that comprises the ring or the stone's mounting base. Touch the magnet to different parts of the ring to see if certain areas are more strongly attracted.

Regards,
ProfHoff 466


I hope you did not pay too much for this ring. Neither platinum, nor diamond is magnetic. It would appear that some metal like nickel or iron was plated with platinum. You should have the ring examined by a certified gemologist.

Vince Calder



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