It has been found as microcrystals with caledonite, leadhillite and
susannite on quartz, and in cavities in etched galena with minute sprays of pale blue lanarkite.
These biggies included matlockite, greenockite, harmotome,
susannite, and others from Scottish localities.
About ten years ago, while on a business trip, I visited the British Museum to look up their specimens of
susannite. I had recently purchased a fine thumbnail-size specimen myself, from Tiger, Arizona, and wanted to compare it to the museum's specimens from Leadhills.