Report on the historical use and development of Garibaldi Provincial Park with emphasis on the Black Tusk and Diamond Head areas, by Katie Bell in 1984.
Of interest is a paragraph on page 2 that summarizes First Nations use.
The local Indian tribes did not establish any known camps or set up any structures in the Black Tusk and Diamond Head areas of Garibaldi Provincial Park. The only known use of the park area by Indians was for obsidian which they may have gathered in the Ring Creek area of Diamond Head. A few legends about Mount Garibaldi and Garibaldi Lake have been documented. Evidence appears to indicate that the Indians had little else to do with the area.
References for the above paragraph are cited from Parks and Outdoor Recreation Division, Ministry of Lands, Parks and Housing Collection of Obsidian from Ring Creek, October 5, 1976 and Vancouver Art, Scientific and Historical Association, Museum Notes, Vol VI, No. 3, September 1931.