It’s easy to redeem Bitcoin Casascius for their underlying value in Bitcoin. Each Casascius has a unique Bitcoin address printed on it, which is also stored on the blockchain.
To redeem a Casascius, simply send the Bitcoin to the address printed on the coin.
The value of each Casascius is backed by one physical Bitcoin. By redeeming your Casascius for Bitcoin, you are essentially exchanging your physical coin for the digital currency.
To ensure the safety of your investment, it is recommended that you redeem your Casascius directly to a personal Bitcoin wallet that you control. This will ensure that you receive the full value of your coin, and that you have sole control over your private keys.