The real cantilever tour de force was the V15-V stylus, which was a 0.5 mil thick beryllium tube 20 mil in diameter. They made that out of beryllium shim stock cut to tiny size, and rolled it around a rod in a miniscule jig. Put it in an annealing oven to stop it just springing open and take a set, and then adhesively bonded the overlap and took the rod out. It calculates out as over 4 times stiffer than a current generation boron cantilever in megabuck moving coil cartridges.
US patent 4,473,897 from 1984 describes the beryllium cantilever manufacturing process.
Then Shure lost faith in vinyl when CD came in, and lost all the beryllium tube know-how and junked the kit. So all they can do now is bog standard aluminium cantilevers.