I think (and I could be wrong) but a very large portion of the queens wealth is held in trust for the benefit of future monarchs..therefore artworks, jewellry, estates, land etc etc etc just passes from one monarch to the next....there will of course be substantial wealth other than these assets, however im not sure whether she has "volunteered" to pay inheritance tax. You can bet that she has the top solicitors to ensure that her estate will payas little as possible.