>The reports I've seen said that the materials, when looked at under a
>microscope, looked like they were made up of bazillions of microscopic
>welds.
>
>This would necessitate a welding machine the size of bacteria, eh?
Making materials by welding together bazillions of microscopic pieces is
called 'sintering' and has been done for at least 200 years. You can sinter
metals or ceramics. Needless to say, it is not done by bacteria with
oxyacetylene torches. You take a powder, you put it in a mold, heat it,
compress it, all the grains weld together, cool down, knock it out of the
mold, and you're done. Keeping the powder from melting entirely is the
tricky part; you need good control of temperature and composition.
--CarlF