For precious metals, the “blockchain” is nature and natural law. Holding gold in your hands requires no reference to a block of bits or bytes to tell you what you own and requires no future exchangeability to establish its long-run value. It’s weight, its elemental classification, its ability to resist entropy, its cost in energy, are all endowed by nature. It’s utility as a commodity money, jewelry money, or its optional input value as a commodity in the production of goods is what sets the marginal demand through time. To its owner, gold is more valuable at rest than it is in an exchange.