Abstract: Found at a small prospect in the Artillery Peaks area, Arizona. Luddcnite occurs in oxidized Cu-Zn ores with fluorite, alamosite, and cerussite. Colour nickel green, H = 4, G meas. 4.45.

Strongest X-ray lines are 7.361(10), 3.173(10), 2.918(8), 5.218(7), 4.226(5), 3.411(5), 2.888(5), 3.650(4). A possible cell found by Ito method is a = 7.85, b = 20.06, c = 14.72 Å, β = 90.78° (monoclinic). Optically (+), α = 1.852, γ = 1.867.

Chemical analysis by wet methods gave CuO 13.2%, PbO 35.1, SiO₂ 25.7, H₂O 20.5, TiO₂ (leucoxene impurity) 4.7. Not all water need be essential, hence Cu₂Pb₂Si₅ O₁₄·nH₂O. The new mineral and name have been approved in advance of publication by the Commission on New Minerals and New Mineral Names, IMA.