It just rolled down the card board really. It seems to have an outer layer that is dark gray. When I went to try it a second time I split the bubble and out oozed a good sized blop of really shiny metal. Assuming that the inside would have been the tin? Since I already made a batch of stannous using this solder mix, which I had to filter because of a similar looking gray matter collecting in small particles, do you think this stannous would be good or is there a specific reason the flux would mess it up. I am just finishing AP as my first experiment on some fingers and connector pins (it is not even eating at the pins) so I don't believe that I have gold in a solution? The stannous test is negative but now I am starting to wonder. Good thing I saved a decant I did on some poorly ground IC chips. Thanks for any input.