In 1890 he was recruited by Dr. James Douglas of Phelps Dodge (PD) and began his long mining career in the Southwest borderlands.

In 1891, Douglas appointed Ricketts manager of the Commercial Mining Company (Phelps Dodge owned) to introduce the Southwest's first Hunt-Douglas process leaching plant at Copper Basin, near Prescott.

The company, backed by Phelps Dodge, also acquired claims adjacent and above the rich United Verde mine at Jerome.

The failure educated him not to build a costly mill before opening an ore reserve large enough to pay the bills, let alone make a profit.

As first manager of The Moctezuma Copper Company, Ricketts planned and constructed a modern mine, concentrator, smelter and townsite, connected by railroad.

[9] In 1901, he opened office as a consultant and became legendary for his designs of major metallurgical works during the early twentieth century copper boom.

[13] Also significant was his work, with John Campbell Greenway, in developing the innovative copper-leaching technology with electrolytic refining for ore from the New Cornelia mine at Ajo, Arizona (1911-1916).

[17] In 1940 he was awarded the gold medal, named after his mentor James Douglas, of the American Institute of Mining, Metallurgical and Petroleum Engineers.

He retained his connection with Arizona, being chairman of the Valley National Bank, Phoenix, and a director of Phelps Dodge at the time of his death.