Thick coax is 10base-5
(Thin is 10 base-2)

10 base-5 standards state a "thick" segment should be no longer than 500m (hence the 5 in 10 base-5...)

as for cost, I have no idea, never used it, and most probably never will...

The thing is, signal propagation speed in teleco purposes isn't quite as important as througput (and distance...)

So eventhough thick as higher propagation speeds, the clear winner is still fiber, because of throughput and range...

Ammo