I agree with Pat, looks like cherry sap.  I have tried to make pitch with that sap, but it would not liquify when heated with a tea light the same way pine sap does.  As a result, I scrapped the attempt, especially in light of how easy it is to collect all the pine sap I might need from the woods around me.  Never tried to make cherry sap varnish so I cant comment - but the same holds true - - it is easy for me to get pine sap, so I never bothered with the cherry.    
Russ