A photograph postcard showing the Denver & Rio Grande Western (DRGW) 1704, 4-8-4, on a passenger train No. 5, "Exposition Flyer", passing through Tunnel #28, just east of Pinecliffe, CO, 25 mph.

A photograph print showing Denver & Salt Lake (D&SL) 303, 4-6-0, on passenger train No. 2, eastbound, above Pinecliffe, CO, 2 cars.

A photograph print showing Denver & Salt Lake (D&SL) 303, 4-6-0, on a passenger train, taking on water at Pine Cliff, CO.

From Introduction: "Scattered throughout the Colorado Front Range, there are many small copper deposits, believed to be of pre-Cambrian age. The have been widely prospected but have produced little or no ore. In one of these, the Copper King mine, near Gold Hill, Colo., nickel was discovered in 1930, and development in the following years has exposed some 25,000 tons of ore containing from 2 to 3 percent of nickel. No other nickel deposit is known in the Front Range, but a somewhat similar deposit has been opened in Gem mine, near Canon City and about 120 miles south of Gold Hill."

Postcard from Mabel to Mrs. M. E. Wise, thanking her for her letter, sending her apologies that Mrs. Wise's father is unwell, and promising to explain why she will be unable to visit Boulder, Colorado until February. The front of the postcard features a photograph of two women standing on a large rock inside a dark cavern. Both women are wearing trousers and t-shirts, and the woman on the right has her hair pulled back into small draped turban. They are illuminated by a light from somewhere on the ground, which also reveals the large rock formations on the cave wall behind them. At their feet is a sign that reads, "Visit Cascade Caverns." The name of the cave, "Tobacco Room," is printed at the top of the postcard.

Report issued by the U.S. Bureau of Mines on sub-bituminous slack from Denver, Colorado. The characteristics and properties of 2-1/2 inch slack samples are listed. This report includes tables, graphs, maps, illustrations, and photographs.