Only very top of bottom clay taken. Total yearly production of raw clay is about 20,000 tons. Checking with Richardson (1915) this clay is in Dawson arkose. Richardson thinks Celher clay is too. I would guess it is in upper 1/2 of the formation but prob. below the Budesitic leases. The formation over the clay is coarse arkosic ss and cq, ss with pebbles up to .5 and some still with xl form. This rests discordant on the clays and eats them out locally in channel deposits that trend southeastward For further remarks on Dawson see card on Richardson 1915. Whisenhunt mentions a few other openings in this clay. Robinson took some from nearby, just north of Johnson mine, near l2oz-capped butte, about 5 years ago but no longer uses it. Some openings west east of Hwy 85-87 in vicinity Castle Rock but clay not 'fat' enough here. Also once mined near Lertspur.