If Ulms suggestion is accepted then there is no need to actually ban the dust, as it will be unobtainable anyway. In any case, our research smiths have shown that mere physical contact with the gems is enough to obtain what is being referred to as a 'surface high' [Internal Report TH: D3gemr5.4], and banning the dust does not take the matter far enough.
No, segregation of the gems is what is called for here, and only the nation with the most experience in dealing with gems generally should be the nation to house these dangers while research continues. Nations refusing the safe housing of their death gem stocks should be regarded with at least suspicion, that they are a nation soon to be over run by mindless dust huffing zombies. Negotiations with these nations needs to be carefully considered, as the sanity of their envoys would be in question.
Ulm will provide detailed reports of the condition, number, and storage of all death gems until such a time as they can be safely processed into non-dangerous material.
The list of nations currently participating in this program shall follow:
Ulm (6 death gems, good condition, safely stored)
Yomi (5 death gems, slightly scuffed, safely stored)
Vanheim (10 death gems, 3 clearly shaved, safely stored)
Remaining vault room for 137 gems.
You do not want to not be on this list.