Some of ya'll are looking for a way to further refine heavily carded kif, and one way that works for small personal quantities, is electrostatic separation using a sheet of parchment paper wrapped around a DVD movie case to hold static charge.
You wrap the paper and hold it tight like this:
DVD Cassette wrapped with parchment paper
Next you drag the kif back and forth across the screen using the wrapped case held perpendicular to the screen. You repeat holding the case at 45 degrees.
Hold at 45 degree angle
Using a soft camel hair artists brush, clean off the foreign debris stuck to the leading edge of the case, as well as the bottom.
After tapping to clear the bristles, use the same brush to brush the heads electrostatic-ally stuck to the back side of the case.
Not a fast process, but one which delivers good results in personal use quantities.
Here is an expired patent for a Multifield electrostatic separator, that runs a conveyor of the material under an electrostatic-ally charged rotating drum. The goodlets are attracted to the drum, and are subsequently harvested using a brush to dislodge them and a vacuum knife to collect them.
Electrostatic separator patent: http://www.patentbuddy.com/Patent/4363723
Electrostatic mining link: http://mine-engineer.com/mining/minproc/elstat1.htm
Dry Ice sieving: http://www.plantphysiol.org/content/plantphysiol/99/1/1.full.pdf