annual quantity of metal to be minted. == Fiscus''' incomes == The incomes of the emperor's chest could derive from taxes or from other sources. Incomes from taxes The first noteworthy tax is the provincial tax imposed to the imperial provinces. It is essentially a 10% of the entire amount of taxes due, imposed only on those able to generate profits (females, children and old people were not subjected). These incomes were especially used for national defense. There was also the vicesima hereditatium, a tax of 5% of the inheritances. Another important tax was the dogana, with a variable percentage going from 1.5% up to 5%. Luxury objects imported from the east, for instance spices, silk and precious stones were subject of a customs tax 25% of their value. The last one was on the turnover, but it isn't known in which measure. Non-fiscal incomes Incomes received as inheritance by the emperor. This type was one of the most relevant income's sources for the fiscus, it was a custom among the Romans to leave as inheritance something to the emperor. The lost portion of an inheritance (bona caduca), that is the part of the inheritance that couldn't be received by the heir. There were some reasons for which someone couldn't receive the whole inheritance or part of it. For example, the Lex Papia Poppea Nupitalis (9 BC) established that some people couldn't inherit, namely: the caelibes (unmarried men between 25 and 60 years old and unmarried women between 20 and 50 years old) they lost the 100% of their capacity to inherit, the orbi (married people without sons) who lost the 50% of their capacity to inherit, the pater solitarius (i.e. who had sons from a previous marriage but didn't marry again) for them the lost capacity isn't known. There are also laws concerning the unworthiness of the heirs. The vacant inheritance (bona vacantiaia), that is the case in which the inheritance was without any heirs, neither legal nor designated. If the deceased was a citizen of one of the imperial provinces the fiscus became owner (but, in this case, it also inherited any eventual debts). The inheritance of the “implicit guarantor”. Is a very peculiar kind of guarantor who was relevant in case the deceased asked him (but with an unspecified formula) to transfer the inheritance once received. This disposition was meant to avoid the use of this figure,