Copper dust 5877:49 Buildcraft additions can not be melted in tinkers construct.
And you need Tinkers copper to make Brass. :| Know there is work arounds but still...
Seems pointless to dust -> furnace to get a galacticore -> tinkers -> brass
There is an item ingame that's called "Ore Converter", pretty easy recipe (1 crafting table, 1 cobblestone and 1 ironingot) and you can then switch around the different mods you want to use the ore from.
Seen on the duster from Buildcraft Additions:
Maybe it could be possible to add recipes for hardened redstone/lapis/diamond/emerald/quartz?
For ore it would bring nothing (since it would kill the thought of hardened ore being less worth than normal ore) but for the fixed amounts of redstone etc. (since fortune not works on hardened ore) it probably would be a nice idea to add their recipes to the duster to maybe get +1 or +2 when it comes to diamond and emerald and maybe +4~+5 for redstone/lapis/quartz. (numbers up to you of course, just as suggestion what could work, making the dusters worth the jumping ^^)
So, even with fortune not working on them, you would have a way to bring a bit more out of them when you're using silktouch to collect them and work with the new machines. (for ore they're pretty useless at the moment, since you can double the normal ore in the tinkers' smeltery anyways, so no need to get them through the dusters but for eureka)