Dampen with 50/50 water/alcohol as it is rolled over a (chlorate) core star or stars containing NO sulfur or sulfur compounds. It helps to slightly dampen the lampblack with pure alcohol before it is mixed with the other dry ingredients. Once thoroughly mixed, it should still flow as a powder, or too much alcohol was used. If that happens, allow it to evaporate for awhile until it can be sprinkled on the rolling stars.
PML, post by Bill Ofca <firstname.lastname@example.org