The information below has been compiled from a variety of sources. If the reader has access to information that can be documented and that will correct or add to this woman’s biographical information, please contact the Nevada Women’s History Project.

At A Glance:

Born: December 4, 1879
Died: 1970
Maiden Name: Grenz
Race/Nationality/Ethnic Background: Caucasian (German)
Married: Joseph P. “Perry” Clough, Max Magnussen
Primary City and County of Residence and Work:
Winnemucca (Humboldt)
Major Fields of Work: Mining (promotion, prospecting), Real estate
Other Role Identities: Wife, Aunt, Hairdresser, Housekeeper


Mary Louise Grantz (Grenz) was born on December 4, 1879 to German parents who farmed at Tigerton, Wisconsin. According to author Sally Zanjani, Mary couldn’t wait to leave the farm, and early in her life began working for a local doctor. A scandal ensued when she was accused of having an affair with the doctor, after which she left town in disgrace with her sister Emma. The two moved to Florida where they both became hairdressers. From there, they moved to Montana. Mary’s brother, Walter, and his wife had homesteaded a ranch near Butte and her sister, Emma, taught school nearby. Emma met and married a shoemaker and returned to Wisconsin, but Mary stayed in Montana with her brother and his family.

Records indicate that she probably met her first husband in Montana. Joseph P. “Perry” Clough formed a corporation while in Montana called the Northern Nevada Charleston Hill Mining Corporation. It seems they both moved to Nevada about the same time, because when Mary staked her first claims in 1919, Perry also had claims recorded, and it wasn’t long before they were married.

Mary, along with her husband, was very aggressive in promoting their mining property as well as real estate they owned in Florida, Arizona, Seattle and Oakland. They traveled on promotional tours and enjoyed the good life along the way. Mary was known for always being well-dressed and enjoying expensive clothing and jewelry. Perhaps it was her taste for riches that earned her the nickname “Queen Mary.” Or perhaps it was her unapproachable personality that earned her the title.

No doubt her promotional efforts did not help her reputation. Relatives who invested and lost money were not complimentary to Mary. Her sister, Emma, brought her family back to Nevada to help operate the Charleston Hill mine. They were struggling to make a living while Mary was enjoying the finer things in life on her promotional tours. Finally, Emma and her family moved to Seattle where Emma died of cancer. By that time, Mary’s family was so disgusted with her that her father refused to have anything more to do with her.

By the late 1930s, Mary’s situation quite different. Perry had died and their mines were not producing. To earn a living, Mary moved to San Francisco and worked as a housekeeper.

Like many others, her fortunes took a turn for the better with the arrival of World War II. Suddenly, the world needed magnesium and tungsten, and Mary had mines which could produce it. Her Black Diablo mine produced an estimated 90,000 tons of magnesium and probably earned her $150,000. However, true to the gambling nature of miners, she lost most of her fortune from magnesium and tungsten through further prospecting. One of Mary’s prospecting partners, Duane Devine, described Mary’s prospecting to author Zanjani:

Mary would work her way up a gulch or a hillside, looking for float, trying to trace any float she found to a ledge, doubling back when the disappearance of specimens suggested that the ledge might be somewhere behind her….”She was pretty wise on that line. She done pretty good on that for a lady. And she wasn’t scared—she was a working little scamp….No grass growed under her.”

In spite of her mining knowledge, Mary was known around Winnemucca as a woman who kept to herself. Alienated from most of her family, she had grown close to her brother’s son, Leon. When Leon married, Mary apparently took offense, and then was left with only one niece who stayed in contact with her. June, daughter of Emma, made an annual visit to the Charleston Mine. Finally, in her later years, Mary married for companionship a handsome man, Max Magnussen, who was 25 years younger than she. She also continued to lose money on her mines by making large, unwise, investments in equipment that she thought would help her mines become productive.

During this period of time, another woman miner named Josie Pearl was also operating in the area around Winnemucca. Local residents agree the two were competing on some level to be the best woman miner in the area—a competition to become the “Queen Bee,” according to Zanjani. Although Mary’s World War II successes won the competition for wealth, Pearl’s easier personality resulted in more recognition and fame.

Biographical sketch by Victoria Ford

Sources of Information:

  • Zanjani, Sally, A Mine of Her Own, Women Prospectors in the American West, 1850-1950. Lincoln and London: University of Nebraska Press, 1997.