Unconfirmed -> Confirmed -> Converted
Recently found blocks appear in your coin balances and "Bitcoins unconverted (approximate)" total (newly Unconfirmed).
Mined blocks mature and are considered confirmed by the network (transition from Unconfirmed -> Confirmed).
Confirmed coins are ready to be sent to the exchange and traded to BTC (or are in the process of being sent/traded).
When coins are traded, the earnings log record the coins converted and total BTC made (transition from Confirmed -> Converted).