Maps. Colorado. Map showing construction materials and nomnetallic mineral resources of Colorado, compiled by D. M. Larrabee, S. E. Clabaugh, W. R. Griffitts, E. C. Fischer. E. L. Fox, R. P. Bryson, R. A. Weeks, D. J. Varnes, and L. S. Rolnick. Scale 1:500,000, scale 10 m.=1.3 in. n. p.