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Cold-weather Jewelry

Not Freezing the Earlobes
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The thermal conductivity of most metals is pretty good. The thermal conductivity of Carbon-60 isn't - less than a twentieth as efficient for most materials that you're likely to find in jewelry.

This morning my wife eschewed her dangly earrings because it's going to be cold all day. I suggested fur earrings, but she doesn't have any.

If the posts of earrings were made of Buckytube bundles, and the backs of such jewelry were lined with layers of C60, they wouldn't be as effective at pulling heat out of earlobes, nipples and whatnot.

elhigh, Nov 16 2007

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       What about cast aluminium? My saucepans have cast aluminium handles, which seems to be a pretty poor conductor of heat. Could this jewelry also be advertised as safe to wear in lightning storms?
hippo, Nov 16 2007
  

       Aluminum is VERY heat conductive - Revere uses it on the bottom of their pots as a substitute for the much-more-expensive copper to even out the heat distribution.   

       Why your cast aluminum handles don't get hot is beyond me - perhaps there is an interface at the handle-to-pot junction that prevents easy transference of heat?   

       If the handles are hollow, that will also slow conduction down.
elhigh, Nov 16 2007
  

       If you're going out and about in lightning storms, I don't think your jewelry is going to make much difference as to whether you get struck. I have a large amount of steel, copper and whatnot all over me: hat brim reinforcement, Leatherman, steel and titanium watch, steel toes in my boots, titanium glasses frames. I'd say I've got more metal on me than 95% of pierced individuals, and some of the most massive bits are in direct body contact.   

       You could make an awful lot of really big nipple rings out of my glasses frames.   

       I don't want to think about what you could do with - or where it would be applied! - my watch.
elhigh, Nov 16 2007
  

       [elhigh] Sorry - I meant cast stainless steel.
hippo, Nov 16 2007
  

       Prince Albert will be pleased!
4whom, Nov 16 2007
  

       Metal pot handles generally stay cool because they are good heat conducters. They are long enough that the heat is dumped to atmosphere before it reaches the primary handling area (just don't grip to close to the pot). This would not work for jewlery where the concern is atmospheric exposure.
MechE, Nov 16 2007
  

       Before anybody jumps on me about it, I remembered correctly: buckytubes are good conductors axially, but not radially: they conduct heat along their length very well but not across their thickness so much. So the post will do a fine job of equilizing the temperature of the fronts and backs of the jewelry, but not so readily conduct heat out of the flesh of the wearer.   

       [hippo] - cast stainless? Sounds pricey, but not inappropriate. Stainless is one of the poorer conductors among the more common alloys. I like cast iron myself, and a good seasoning for rust prevention.   

       And yes, those handles get very hot.   

       [4whom] - Prince Albert had better be into doing lots of lunges - my watch is a Seiko Kinetic.   

       That or he just plays with himself.
elhigh, Nov 16 2007
  

       Eww. I always knew we should have gotten prince albert in a can while we still could.   

       I don't think a carbon nanotube, a fullerene tube, a buckytube, or whatever else you want to call it would be a good candidate for use as a body piercing stud, since it's all floppy, and makes an ideal cheese cutter. These properties may continue to exist no matter how many tubes you line up.   

       Have you thought about fiberglass, plastic, or ceramic materials? A lot of these are getting about as rigid as metal, but are much better at resisting the flow of heat.
ye_river_xiv, Nov 16 2007
  

       You sure about it being floppy?
elhigh, Nov 16 2007
  

       "These properties may continue to exist no matter how many tubes you line up." ~ ye_river_xiv   

       That really is not true. It depends how you structure your end product. However, the conductivity along the axis of nano-tubes is true. Also they do not conduct radially (perpendicular to the covalent bonds). This gives you certain benefits, but also restraints. You would have to *wind* your nano-tubes into a helix-type arrangement. Last time I checked this was prohibitively expensive.
4whom, Nov 16 2007
  
      
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