Wiktionary
keweenawite
n. (context mineral English) A copper ore and discredited mineral species composed of arsenic, copper, nickel, and cobalt.
Wikipedia
Keweenawite
Keweenawite is a discredited mineral species. It was described as an arsenide of copper, nickel, and cobalt containing 39% to 54% copper, 9.7% to 20% nickel, and 0.9% cobalt. Keweenawite was discovered in July 1901, in the Mohawk Mine, Keweenaw County, Michigan. George A Koenig analyzed and named the copper ore.