The Navajo word for sand paintings means "Place where the Gods come and go." The sand painting has been used for centuries in religious rituals, including healing ceremonies performed by Navajo medicine men. A sand painting for a ceremony is made on the ground in the ceremonial hogan and destroyed at the end of the ritual. In order to preserve this long standing tradition, in the late 1940's Navajos began to create permanent sand  paintings, changing the designs slightly to protect the religious significance when these paintings were shown publicly. Pictorial sand paintings which reflect the Navajo environment and lifestyle are made. Sand paintings are made by slowly trickling sand through the hand into epoxy-covered particle boards, using sand made from naturally colored crushed rock, stone, and minerals for shade and colors.