i have a question for you.
where did you get your nitric acid and can you get more?
There are a few companies that will send you the naughty strengths fully legally too. Although they do have a £50 minimum order value (so worth getting a few other interesting supplies at the same time). So long as you are reasonably honest and tell them that you want it for home chemistry and maybe list a couple of appropriate experiments they will sell it to you.