BlackCoin started of as a Proof of Work coin but has evolved to a unique version of Proof of Stake. Wallet users can unlock wallet for staking only. BlackCoin features the following specifications: - Extremely secure: Among first with fix on SSL heartbeat, Transaction malleability, BIP66 - The probability to sign a block and the block reward does not depend on coinage (anymore). - Recommended confirmations: 10, maturity: 500 - Minimum transaction fee: 0.0001 BLK - Defined block time target: 64 seconds - Max reorganization depth: 500 blocks - Inflation: about 0.95%. - PoS block reward: 1.5 BLK + fees - The accumulated reward is proportional to the total balance and the time of staking. 24/7 staking at current network weight leads to an expected reward ratio (interest rate) of about 5%. - BlackCoin rewards users who supports the blockchain through continuous staking.
Novacoin is a hybrid Proof of work (POW) / Proof of stake (POS) decentralized peer-to-peer cryptocurrency.The Proof of Work part of Novacoin is based on the Scrypt hashing algorithm. Proof of Stake contributes to the coins energy efficiency, as there is no need for nodes to contribute mining power to part of the money creation process. As of now, Novacoin is set to be capped at 2 billion coins. However Novacoin stated that the cap limit may be lifted if the situation requires it. It looks very much like a variation of Sunny King Peercoin.