bought an engine of a prominant engine shop thats been around 40 years.
i paid for a scat forged crank and i think its a cast 9000 series $300 crank.
not happy this looks like a cast crank,, chinese garbage scat sells
It's pretty tough to tell from the photo if the machining removed the parting lines from forging dies or removed the parting lines from casting molds. Since they all begin with a cast billet, it's even tougher to tell. Unless there are other hints in other areas of the finished crank, about the only way I know to determine with any certainty would be to cut off a piece and perform a micro crystaline structure analysis under a SEM - And then you'd be buying a different (whole) crank anyway. Since the alloys used can vary a LOT in the aftermarket, other types of testing might be useless and even the structure analysis could be confusing.
I have a Scat cast crank in my Ford 408W. It has a part number engraved in the front counterweight. If you are concerned, pull the oil pan and have a look. Mine looks like this, I assume a Chevy crank would have similar markings.