aka Seven Came Back

Story, first published: Amazing Stories, Oct. 1950
as Seven Came Back

An archeologist, exiled in the desert by his crooked guides, makes friends with the Martians who treat him to a vision of a Martian New Jerusalem, a "shining city on Mars as it once was." When the guides arrive, they find the mummified body of the archaeologist, but their glimpse of the city is only a mirage.

Ewald, Robert J.: When the Fires Burn High and the Wind is from the North, p.58