How does one spot a recast?
Most metal figures are technically recasts, if using master and production moulds. You sometimes see 2 lines on legit figures.
Also, eg. Reaper ask you to send in old figures to be recast, instead of their staff having to trawl through old moulds looking for one figure. So you'd be buying a legit recast, possibly essentially identical to a dodgy recast. They may have even changed metal.
If a figures well moulded and we'll cleaned? How do you tell? If a new legit cast was used and same, at least weighted, metal?
Metal typically used a talc release, so you could test the talc, metal and any silicon remnants on the figure.
Looking for shrinkage or distortion from being pressed may help.
If it's a straight cast, air escapes and metal inlets (whatever the technical terms are) could be telling. I've seen both very neat work (from a chap above) and less neat.
If they are painted, it's harder to tell. Try weighing them, but basing, even paint may put it off. You'd have to probably strip it to be sure of weight, even then some excess flash or line may affect it.
Warming. Here's an idea. Get a legit and suspect cleaned figure. Warm them the same then test their temp a minute or so later. Just made it up, but if the metals are different, so should the temps, I guess?????
Again, like Reaper, some comps may do legit recasting, even using different metal. Sometimes a master mould could be damaged or lost and existing products may be simply recast, again legitimately.
I'm sure there's more to it all.