HP48GX, small blue dot in the LCD

[grsbanks]

That's probably it.

I recently bought a 50g that was in great condition but when it arrived it had a series of similar blotches on the LCD. I took the batteries out and left the calculator face down on a radiator for a few hours to "bake" the blemishes out of the LCD and it worked perfectly. They went away and have not come back since. It would have been unfortunate for a blue 50g to have that defect!