The LASSIE uranium showing is located 500 metres to the west of Lassie Lake and approximately 10.2 kilometres northwest of the Kettle Valley community of Christian Valley.
The showing is underlain by metasedimentary rocks of the Carboniferous-Permian Anarchist Group and granodiorite and diorite of an unnamed Middle Jurassic intrusion. These are overlain by the Miocene-Pliocene Chilcotin Group, which consists of an olivine basalt and tuff breccia, up to 100 metres thick, and minor basal conglomerate. The basalts and conglomerate were deposited along a northeast trending paleovalley.
The property was staked in 1975 for Nissho-Iwai Canada Ltd. who carried out a 5-hole, 738 metre diamond-drill program in 1976. Anomalous radioactivity was identified in hole BCF-78. It measured 1000 counts per minute (background 50 counts per minute) on a GP-27 down-hole probe. The radioactivity is mainly associated with the basalt and tuff breccia. Uranium equivalent is 0.028 per cent uranium (Assessment Report 5982).