Guides

How to Send Private Coins to Somebody Else

Zerocoin is and has always been our central feature. Zcoin’s Zerocoin feature allows people to burn (mint) coins, generate a cryptographic proof that they have been burned and use that proof to redeem (spend) an equal amount of coins with no prior transaction history. By breaking the link in the chain of transactions, Zcoin enables private confidential transactions.

To date, this process involved minting coins and spending them to yourself before they could be transferred to another party. Some of you have rightfully asked why you could not directly spend these coins to a third party rather than to yourself. Today, we’re pleased to announce that this is now possible.

How to Mint a Coin

In your wallet, go to the Zerocoin tab, select the Mint button in the lower half of the screen and pick a denomination (number of coins to be minted). The list should now show a New mint.

Zcoin Zerocoin screen

How to Spend a Coin to Yourself or a 3rd Party

Once the mint has 6 confirmations, it can be spent. To do that, please click the Spend button. There you will have the opportunity to choose an address to send the new coin to. This can either be in your own (checkbox Spend to me) or someone else’s wallet.

After having clicked Spend Zerocoin, the coin(s) will be made available to the receiver. In your wallet, this will be registered as an outgoing transaction of 0.00000000 XZC

Zerocoin to 3rd party in Zcoin wallet

However, this transaction is not linked to your wallet in any way! On the block explorer, the transaction will be listed as coming from Zerospend (this example is using another destination address than above).

Zerocoin spend to 3rd party on block explorer

Please note that you can only spend the full amount of the denomination for now. This is because with the current wallet, spending a fraction of a mint could potentially de-anonymise your transaction. When you spend a fraction, the spend has two outputs: the receiver (3rd party) and a change address in your own wallet. This means that by spending a fraction, you have now linked the 3rd party spend to your own wallet. Solving this issue is one of the big changes (next to an all-new and beautiful UI) coming to our upcoming wallet – so stay tuned!