NXT is one of the early cryptocurrencies and was started in 2013. As the Jelurida project’s website states, it was the “first to rely entirely on the PoS protocol”. It is currently listed by the number of exchanges.
Comet (CMT) cryptocurrency is formally accounted on the number of ratings.. However, there is no up-to-date official information about its current status. Therefore, we can conclude that the coin is currently inactive.