OMG is not mineable because it's based on Proof of stake not proof of work so if I have 5000 OMG tokens and I stake them I will get a returen on them because I am helping in verifying the transactions by staking my tokens.The benefit of POS (proof of stake) is that say I wanted to cheat the system(blockchain) by changing the distributed ledger.If it is found that i have been trying to hack the block-chain (not that its feasible ) then the OMG tokens i have staked will be locked by the block-chain. But you will also be rewarded for staking your OMG and helping the system run just like miners are in proof of Work
POS is the future because this way crypto-currencies can become more mainstream additionally in the future it will become almost impossible for mining to continue mainly because of cost of electricity.
https://www.smithandcrown.com/sale/omisego/
