Sverigeite, NaMgMnBe2SnSi3O12(OH), is orthorhombic, space groupIbmmorIbm2 with a = 6.818(6), b = 13.273(8), and c = 10.815(8) Å. The strongest reflections in the X-ray powder diffraction pattern are: 2.884(202); 2.826(042); 4.35(121); 5.77(101); 2.644(222); and 6.63 Å (020). Chemical analyses yielded SiO233.5, FeO 0.3, ZnO 1.2, MgO 8.1, MnO 11.8, Na2O 6.1, BeO 9.7, SnO228.5, H2O 1.2, sum = 100.4 weight percent, in good agreement with the proposed formula with Z = 4. Sverigeite is yellow in color; the hardness (Mohs) is approximately 6 1/2; the density is 3.60 (meas.), 3.61 (calc)g/cm3; cleavage is perfect on {010}. Optically, sverigeite is biaxial positive, 2V = 67°, with indices of refraction α = 1.678(4), β = 1.684(4) and γ = 1.699(4); dispersion is strong r > v; pleochroism is moderate: X = yellow, Y ≃ Z = pale yellow; absorption X > Y ≃ Z; orientation: Z = b. Sverigeite is found associated with mimetite, jacobsite, manganoan calcite, and amphibole. The only known sample was found on the dumps of the Långban Mine, Värmland, Sweden. This new species is named for Sweden, the country of origin.