Look's like a 50nf Tantalum to me, just a guess. Also being able to view the rest of the device may help. What is the problem? Just want to know or is there a problem in that circuit? I never seen a cap of this design go bad, if it is tantalum it should outlast your lifetime and mine. I would not change it out unless its open or way out of spec. Depending on the circuit this type of cap is very good next to ploypropylene or polystrene.