The North Mooney's zeolite showing occurs within rhyolitic tuff considered to be of Eocene age and correlative with the Kamloops Group to the east of the Fraser River. Zeolite minerals in the tuff have formed by hydrothermal alteration of the rhyolite. There is a spatial relationship between alteration zones and faulting, suggesting that the Fraser and associated faults provided channelways for the hydrothermal solutions.

The showing is an isolated outcrop of layered rhyolitic tuff in generally drift covered terrain. Heating for 16 hours at 525 degrees celsius gave indication that the tuff contains an clinoptilolite-rich intermediate member of the heulandite-clinoptilolite series. Exchangeable cation analyses, expressed in milli-equivalents per 100 grams are: calcium, 28.25; magnesium, 1.13; sodium, 33.00 and potassium, 6.50. The cation exchange capacity (CEC) is 69.9.