Very dirty.
That's the best observation I can make with that photo.
Please clean it and try again.
That's the first I've heard of lead causing throat cracking. How many have you cracked? I've shot predominantly lead alloy bullets through my Smiths, with loads ranging from mild to wild, for over 50 years with no cracking. I'd be interested in your source of that bit of information. Thanks in advance, RodI've cracked my share of forcing cones on the K-Frame S&Ws. Caused by using a lot of lead ammo.
But - - if you can't shoot it or try to replace the barrel isn't that the same thing as fini?Rarely, continuing to shoot a revolver with a cracked forcing cone or even an attempt to remove the barrel will crack the frame and that, boys and girls, is finis for the gun.