The Ridge Zone platinum-chromite showing outcrops along a northwest-trending ridge on the southern slopes of Grasshopper Mountain, 10.5 kilometres west-southwest of the town of Tulameen.

The ridge is underlain by dunite and peridotite of the Early Jurassic Tulameen Ultramafic Complex, a zoned Alaskan-type intrusive complex. The dunite contains relatively abundant chromite in a zone trending northwest for 300 metres and varying up to 100 metres in width. Chromite comprises up to 20 per cent of the dunite in this zone (Assessment Report 17170). The mineral forms irregular lenses up to 20 centimetres long and 10 centimetres wide, fracture fillings up to 2 centimetres wide and primary layers of magmatic origin up to 15 centimetres thick.

Elevated platinum values are found in the southern half of this zone of chromite mineralization, with assays of up to 1.445 grams per tonne platinum (Assessment Report 17170, page 10). Analyses of eight samples taken in the southern half averaged 0.418 gram per tonne platinum (Assessment Reports 15516, 17170). Seven samples from the northern half assayed up to 20 percent chromium, yet yielded less than 0.050 gram per tonne platinum (Assessment Report 15516, page 28, Map 2).

This occurrence was sampled and mapped by Newmont Exploration of Canada Ltd. in 1986 and Tiffany Resources Incorporated in 1987.