These are polish coins:

here's article (one of the biggest internet news portal):

http://wyborcza.pl/1,75478,15707096,PolishCoin__Polcoin_i_PLNc__W_Polsce_sa_juz_az_trzy.html?utm_source=HP&utm_medium=AutopromoHP&utm_content=cukierek1&utm_campaign=wyborcza#Cuk

i thing its worth of diging ...

http://pcc.eminer.pl
http://plc.eminer.pl
http://pln.eminer.pl

exchange https://c-cex.com/index.html?p=plc-btc

to the moon !