Mosesite

Mosesite is a minute yellow crystal with imperfect cleavage along {111} and uneven fracture. It is brittle with a hardness of 3.5. Long exposure, a month or more, to light will change Mosesite to a light olive green color. The powdered form retains its color streaking a light yellow. The mineral exhibits no pleochroism and displays uneven birefringence in polarized light. Heat has a notable effect on Mosesite for when heated above 186 °C (367 °F) the mineral becomes isotropic. This corresponds optically with the observed crystal form only at this higher temperature. It is considered weakly anisotropic. The index of refraction is n = 2.065±0.01. It has an adamantine luster that officially ranges in color from lemon yellow to canary yellow. Mosesite reacts chemically with HCl leaving a residue of HgCl.

Mosesite contains 16 Hg, 3 Cl, 1½ SO4, ½ CO3 , ½ MoO4, 16 H, and 8 N with a volume of 8.4777x10 nm³ and calculated density of 7.53 g/cm³. The accepted formula for mosesite is Hg2N(Cl,SO4,MoO4,CO3)•H20.