[6][7] Other mineral deposits adjacent to the hot springs include gold, silver, mercury, antimony, thallium, and arsenic as reported by Pearcy and Petersen (1990).

The multiple mercury and sulfur deposits in the hot spring area are due to volcanic processes and magma below the surface.

[1][9] Other minerals mined at the Sulphur Creek, approximately one mile upstream from Wilbur Springs, include gold, copper, and sulfur.

The water of the Chromatic Spring fluctuated between reddish purple to bright green to black due to the presence of algae species and mineral content.

[1] The resort website lists chloride, carbonic acid, sulphate, silicate, lithium, manganese, zinc, sodium, potassium, boron, magnesium, calcium and cadmium based on a report from the USGS.

[13] As of 2018, Wilbur Hot Springs resort is the sole remaining business in the Sulphur Creek Mining District.

[2] Before European settlers came, the Native American inhabitants of the Coast Range made use of the springs as ceremonial and healing grounds,[14][15] in particular the Yocha Dehe tribe of the Wintun Nation.

[15] Throughout America in the late 19th century, hot springs became very popular among those who could afford the often long and arduous journeys and the cost of staying at fashionable resorts.

Guests traveled on the Southern Pacific Railroad to Williams, then covered the last 26 miles (42 km) to the springs by stage coach.

[21] However, the hotel at Wilbur Springs was destroyed by fire in 1870, and by 1891 the spa's fortunes were in decline due to an absentee owner and a better property a mile down the road at Sulphur Creek Village.

[22] In 1915, the cabins were razed by the then owner, J. W. Cuthbert, and replaced with a two-story hotel,[23] built in 1918,[10] one of the first poured concrete buildings in California.

In 1968, when the owner was Mildred Sutliffe, a visitor wrote, "The old hotel looks like an excellent candidate for a bonfire, and the baths are little more than rabbit hutches.

"[24] Wilbur Hot Springs was purchased in 1972 by Richard Louis Miller, a Gestalt therapist who relocated his San Francisco clinic there.

[26] The remote resort—for much of the 20th century, the hotel was its own post office, and electric lighting was first introduced in 1993—became known for clothing-optional co-ed bathing.

[23] In 1993 a New York Times travel writer described the hotel as "feel[ing] like a college campus, circa 1968", with guests required to bring their own food and drinking water and cooking meals collectively, quiet hours from 10:00 to 10:00, a single guest telephone in the parking lot, and showers across the driveway.