Y'know, I've oft wondered what the difference between a "pure" crystal cluster and a "mixed" crystal cluster is. If there isn't then I'd wager then it's a bit of a waste then.
Also, Stark Bees. That is all.
Well, OK, maybe not all. You see, Stark Bees are your best friend for getting dull shards. Why? Because you can get said bees without draining ALL OF THE VIS from an area. And they produce dull shards, so Bob's your uncle, Crystal Capacitors for everyone! That is, assuming you play SMP. So it's more like Crystal Capacitors for me... and I guess my cat?