Ramsdellite

MnO₂IMA symbol: Rmdgrandfathered

Ramsdellite is an oxide or hydroxide mineral with the formula MnO2, crystallizing in the orthorhombic system. It has a calculated density of 4.831 g/cm3.

Photos

Ramsdellite specimen photo — Robert M. Lavinsky · CC BY-SA 3.0 · Commons

Crystallography

Crystal system	orthorhombic crystal systemWikidata (CC0)
Space group	P b n m
Cell (Å, °)	a = 4.513, b = 9.264, c = 2.859; α = 90, β = 90, γ = 90
Cell volume	119.53 Å³, Z = 4
Axial ratios	0.4872:1:0.3086calculated from COD 1514109
Source structure	COD 1514109 (Journal of the Faculty of Science, Hokkaido University, Series 4, 1990) — 1 of 6 structures

Powder X-ray diffraction (calculated)

d (Å)	4.057	2.549	2.337	1.654	2.433	2.142
I/I₀	100	67.2	61	54	29.2	21.9

xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 1514109; idealized occupancies, no preferred orientation.

Physical properties

Density (calculated)	4.831 g/cm³calculated from COD 1514109

Chemistry (calculated)

Molecular weight	86.94 g/molcalculated from the IMA formula
Composition (wt%)	Mn 63.19%, O 36.81%

Classification

Nickel-Strunz (10th)	4.DB.15aWikidata (CC0)
Nickel-Strunz (9th)	4.DB.15Wikidata (CC0)