I've seen many claims that the blockchain can be used to provide traceability for various goods but I don't get it.
For one thing this isn't trustless, the blockchain doesn't know what a diamond is so if a person entering a new diamond to the blockchain "database" decides to lie there's no way to prevent it "trustlessly". How do you prevent the same diamond to be entered twice in the chain? How do you prevent somebody from entering a diamond that doesn't exist in the chain? How do you make sure that some physical diamond you have in your hands matches an entry in the blockchain (and one only)? The ledger is immutable but diamonds aren't, what if a diamond is recut and the blockchain entry is not updated to match? What if I decide to "launder" some blood diamond by adding a transaction on the blockchain saying that it was destroyed, followed by a brand new clean entry pretending that I've just mined a new one?
In the end you'd have to trust some sort of authority to put the diamonds on the chain honestly.
So if you have decided to trust some authority, what do you need the blockchain for? Just have the De Beers cartel digitally sign a certificate for each diamond like an HTTPS certificate authority and bundle it with the stone. Exactly the same trust model and you don't have the overhead of the blockchain.
Is there a use case that I'm missing or is it just yet an other occurrence of "let's say we do blockchain stuff and people will throw money at us"?
For one thing this isn't trustless, the blockchain doesn't know what a diamond is so if a person entering a new diamond to the blockchain "database" decides to lie there's no way to prevent it "trustlessly". How do you prevent the same diamond to be entered twice in the chain? How do you prevent somebody from entering a diamond that doesn't exist in the chain? How do you make sure that some physical diamond you have in your hands matches an entry in the blockchain (and one only)? The ledger is immutable but diamonds aren't, what if a diamond is recut and the blockchain entry is not updated to match? What if I decide to "launder" some blood diamond by adding a transaction on the blockchain saying that it was destroyed, followed by a brand new clean entry pretending that I've just mined a new one?
In the end you'd have to trust some sort of authority to put the diamonds on the chain honestly.
So if you have decided to trust some authority, what do you need the blockchain for? Just have the De Beers cartel digitally sign a certificate for each diamond like an HTTPS certificate authority and bundle it with the stone. Exactly the same trust model and you don't have the overhead of the blockchain.
Is there a use case that I'm missing or is it just yet an other occurrence of "let's say we do blockchain stuff and people will throw money at us"?