Hi All

No. No one has quenched it to STP (yet!) but it'd be really interesting to know what would inhibit the decomposition process. Diamond is only meta-stable at STP too, but it takes quite an energy input to get it to revert to amorphous carbon. If carbonia proves as reluctant to decompose as diamond it will be a very handy material indeed.

Diamond anvils aren't a convenient manufacturing system either, so hopefully some one will invent a process as convenient as the new vacuum deposition way of making diamonds. Big, perfect and relatively cheap.

Of course Stephen Gillett was the first to speculate that carbonia might be a convenient form to turn Venus' excess CO2 into, if it's stable at high temperatures and pressures...

Adam