Like everything else, spiritual stones are also subject to the law of thermodynamics. That meant they slowly lost their spiritual charge over time. It seeped into the atmosphere, turned into heat or electromagnetic waves, and dissipated. It left a container that is one of the least conductive to spiritual energy known to man. It is a container that could be melted and made into things that don't conduct spiritual energy.
Wang Feng had qualms about testing things on his own body all the time. He bought a cadaver from which he could make a cardiovascular system cast. Since he didn't have silicone or latex to fill the veins and heart with, he needed a different approach to doing this. He used his karmic blood cultivation sutra, which he created, to map the cadaver's cardiovascular system. Since the cadaver didn't have a heartbeat, Wang Feng's assistant had to massage its heart through the whole process.
