|Making faked eggs|
I find some similarity between this practice of metal changing and a "practice" recently surfaced in Mainland China. I am talking about the "practice" of making faked eggs. There are indeed different ways to accomplish the same objective, some culprits, after being caught or gave themselves up, explained to the authority their special secrets, surely enough, each claimed to have the best techniques! Some even offered tuition for learning their techniques, of course in private and away form the authority.
An undercover reporter from Shandong Province （山東省) paid RMB700 to have a private tuition with an expert in the field named Mr. Ren Yongxing （任永兴). Without knowing the reporter's ultimate objective, the master taught him everything, from ingredient preparation to mold making, telling him that he only needed 30-40 times of diligent in-home practice to make a passable faked egg. And, before the reporter left, the master handed him a CD! The ending of this story? The reporter published the story in his newspaper and the master gave himself up to the police a few days later (see the full story in Chinese through this linkage - with complete photos showing the process).
One however should take note of one important point. Whereas faked eggs makers are for private gains, at least some external alchemists were with the heart of one Robin Hood.