Recipe for NOTE BLOCK is: BLUE BLOCK and OLDE TIMEY RADIO. NOTE BLOCK is in music category. Lunch brake plant. Not for speed eaters though. Not much exp to be gained from breaking this. Hitting it will break it but you need to count the hits yourself. Seed mathematics is very complicated, but you should get at least 1 seed back from splicing NOTE BLOCK. Gemratio of NOTE BLOCK is a mystery. Maybe you can check the wiki for <a href="https://growtopia.fandom.com/wiki/Note_Block">note block</a> Will you get enough blocks to build something? You just have to find out yourself.