I didn't set up the drops but I was under the impression they would be dropping only in Kunark dungeons (maybe not all of them). I'm not at work to double check though so it's possible my memory is failing in my old age. And I equally have no idea at all about the drop rate, but that's something that presumably can be tweaked a bit depending on how things go now it's dropping, so I'm confident that if it looks appropriate to change it, it can be changed. One day is a bit too early to really tell much about the drop rate, so I suggest seeing how it goes over the weekend. If that still seems extremely rare then I can check whether it's working as intended or might be bumped up.
Something to keep in mind too, while it's a high demand item right now because it's brand new and shiny and nobody has one, after half a year when most people who want one have got one, folks in those dungeons are going to be rather irritated if every third drop is a shard and they just accumulate on the broker. If it IS intended to be a low drop frequency item (and once again I don't actually know, and am not at work to check right now) then yes there will seem to be a shortage at first while the rush is on, but it will slowly even out as more enter the world.
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