Happily, it is an attractive mineral, forming yellow prismatic crystals, often in radiating clusters, sort of resembling mimetite.
The unhappy part is that it has only been found in one location
(the Picket-Corral or "Blue Streak" mine) in southwest Colorado.
At least that is the case thus far.
It was only found in one pillar in that mine, and the latest report is
that there is no more to be had.
Note that this mine is both locked (access only by permission) and is partially flooded (so you either need to swim or have good waders).
Tom's Mineralogy Info / tom@mmto.org