MJ> If you have
MJ> ever seen a burnt-out light bulb, the black coating on the inside is
MJ> tungsten that was vaporized by overheating.

G’day; another 0.02 from me. Tne main reason why light bulbs
fail is due to (a) the tungsten filament very slowly vapourising,
and thus making it have a higher resistance to the current, and
(b) oxygen from the atmosphere gettng in and oxidising the
tungsten. Most of the bulb-blackening is tungsten oxide which is
far more volatile than tungsten. Long ago I used to make
tungsten/molybdenum thermocouples for temperature measurement in
high temperature furnaces, and they had to be sealed into pure
silica sheaths,

otherwise they’d soon become oxidised and last no time at all.
So, when you heat a tungsten pick white-hot, don’t do it for very
long. Cheers, –

   / /    John Burgess, 
  / /
 / //\    @John_Burgess2
/ / \ \

/ (___)

Hi again to all orchidians and best wishs for christmas probably my
last topic for this year will be on tungsten. i really want to get
started on making my own tungsten jewelry after many weeks of
research i have come to the conclusion that there is not alot of
tungsten machinnery supplier if anyone knows of such i would love to
know is there a way to have a small production going for a
reasonnable investment of 25K? Anyway i would love to ear about every
experiences, research or price list or suppliers regarding that
metal. Thanx to everyone.


I know there is a guy I think his name is Trent West who is making
tungsten rings, I talked with his brother who thru out some big
numbers on machine and set up cost.He showed me one ring he had be
wearing all the time for months ,it looked brand new not a mark on
it.his rings are a tungsten gold combo. He is selling to fine
jewelry stores with good success.