Secondary mineral formed in the oxidized zone of a U-As deposit.
IMA Status:
Valid Species (Pre-IMA) 1958
Locality:
Dump of the Sophia mine, near Wittichen, Black Forest, Germany. Link to MinDat.org Location Data.
Name Origin:
Named for meta which indicates membership of this species in the meta-autunite group and for Franz Waldemar Kirchheimer (1911-), former Director of the Geological Survey of Baden-Wu rttemberg, Germany.
Name Pronunciation:
Metakirchheimerite + Pronunciation
Metakirchheimerite Crystallography
Axial Ratios:
a:c = 1:1.19498
Cell Dimensions:
a = 7.18, c = 8.58, Z = 1; V = 442.32 Den(Calc)= 3.83
CI meas= -0.191 (Poor) - where the CI = (1-KPDmeas/KC) CI calc= -0.003 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1646,KPDmeas= 0.1955,KC= 0.1641 Ncalc = 1.53 - 1.63
Optical Data:
Uniaxial (-), e=1.617, w=1.644, bire=0.0270.
Calculated Properties of Metakirchheimerite
Electron Density:
Bulk Density (Electron Density)=3.40 gm/cc note: Specific Gravity of Metakirchheimerite =3.83 gm/cc.
Fermion Index:
Fermion Index = 0.0035100956 Boson Index = 0.9964899044
Photoelectric:
PEMetakirchheimerite =1,205.00 barns/electron U=PEMetakirchheimerite x relectron=4,095.52 barns/cc.
Radioactivity:
GRapi = 3,527,063.82 (Gamma Ray American Petroleum Institute Units)
Concentration of Metakirchheimerite per GRapi unit = 283.52 (PPB)
Metakirchheimerite is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.
Estimated Maximum U.S. Postal Shipping Size
(10 mRem/hr limit, Unshielded 10 cm box)
8.62 ± 2.16 grams of pure Metakirchheimerite .
Estimated Maximum U.S. Postal Shipping Size
(10 mRem/hr limit, Unshielded 100 cm box)
862.38 ±215.59 grams of pure Metakirchheimerite .
Estimated Radioactivity from Metakirchheimerite - very strong
Specimen Size Weight/Volume (Sphere) *
Calculated Activity Bequerols (Bq)
Calculated Activity Curies (Ci)
Estimated Activity GR(api)
Estimated Exposure (mRem**)/hr If Held in Hand For One Hour
1000 gm / 7.93 cm
83,465,801
2.26E-03
3,527,063.82
1,159.58
100 gm / 3.68 cm
8,346,580
2.26E-04
352,706.38
115.96
10 gm / 1.71 cm
834,658
2.26E-05
35,270.64
11.60
1 gm / 7.93 mm
83,466
2.26E-06
3,527.06
1.16
0.1 gm / 3.68 mm
8,347
2.26E-07
352.71
0.12
0.01 gm / 1.71 mm
835
2.26E-08
35.27
0.01
0.001 gm / 0.79 mm
83
2.26E-09
3.53
0.00
Weight of pure Metakirchheimerite in grams (gm) and Calculated Diameter of a Sphere with a Density of 3.83 gm/cc.*
Goverment Estimate of Average Annual Exposure (
360 mRem)
** Note: 10 microsieverts/hr = 1 mRem/hr **
Max Permissable Adult Dose 50,000 mRem/yr (hands), 15,000 mRem/yr (eyes)
Lethal Dose LD(50) Exposure 400,000 to 500,000 mRem
Chemical Formula: 
- very strong