What is "stonemasters"

The Stonemasters were a group of rock climbers and adventurers in the early 1970s originally based out of Southern California—principally Tahquitz and Suicide Rocks, and Joshua Tree—and, later, Yosemite National Park. The initial group consisted of the following members: Rick Accomazzo, Richard Harrison, Mike Graham, Robs Muir, Gib Lewis, Bill Antel, Tobin Sorenson, John Bachar, and John Long.