Rutherfordine

  • Diderichit
  • ( UO2) (CO3)
  • [ UO2 | CO3 ]

Rutherfordin is a rarely occurring mineral from the mineral class of " carbonates and nitrates " (formerly known as carbonates, nitrates and borates, see Classification ). It crystallizes in the orthorhombic crystal system with the composition ( UO2) (CO3), and is therefore chemically seen a uranyl carbonate.

Rutherfordin found mostly in the form of dense to powdery masses of uraninite ( UO2), but also make radial- fibrous felt-like aggregates up and rarely afford crystals to about three millimeters in size. Its color varies from light yellow to almost white, straw yellow to greenish yellow or orange to amber brown.

Special Features

The mineral is characterized by its uranium content of up to 72.12 wt - classified as very highly radioactive % and has a specific activity of about 129.1 kBq / g (compared to natural potassium 31.2 Bq / g).

To have belonged to 1954, Hans W. Bültemann fluorescence analytical studies of secondary uranium minerals by, including a strong green fluorescent Rutherfordin from the Morogoro (Tanzania ). However Bültemanns observation could not be confirmed by synthetically produced substance and thus pure Rutherfordin. A due to the composition rather improbable fluorescence would thus be only the result of foreign admixtures and secondary mineral formation in naturally formed Rutherfordinproben.

Etymology and history

Rutherfordin was discovered on the western slope of the Lukwengule in Ulugurugebirge in Tanzania and 1906 for the first time by the German chemist Willy Marckwald ( 1864-1942 ) described, who named the mineral after the famous nuclear physicist Ernest Rutherford to honor his services to the study of radioactivity.

Classification

In the now outdated but still in use 8th edition of the mineral classification by Strunz the Rutherfordin for common class of carbonates, nitrates and borates and there belonged to the department of " Uranylcarbonate [ UO2 ] 2 to [ CO3 ] 2 - ", where he with Blatonit, Joliotit and Oswaldpeetersit the unnamed group V/F.01 formed.

The 9th edition used since 2001 and valid by the International Mineralogical Association (IMA ) of the Strunz'schen Mineral classification assigns the Rutherfordin in the shortened class " carbonates and nitrates ," there but also in the department of " Uranylcarbonate " one. However, this is further subdivided by the molar ratio of uranyl carbonate complex to so that the mineral according to its composition in the subsection " UO2: CO3 <1: 1-1: 2" to find where it is the only member of the unnamed group 5 EB.05 forms.

The mainly common in English-speaking classification of minerals according to Dana assigns the Rutherfordin as the outdated Strunz'sche systematics in the common class of " carbonates, nitrates and borates " and there in the department of " water clear carbonates " one. Here he is the only member / along with the unnamed group 14:01:04 within the subdivision " Anhydrous carbonates with a simple formula A CO3 " to find.

Education and Locations

Rutherfordin forms as a typical secondary mineral weathering of uraninite. In addition to this may occur as more parageneses, you still Becquerelit, Billietit, Boltwoodite, Curit, Fourmarierit, Kasolit, Masuyit, Metatorbernite, Schoepit, Sklodowskit, studtite and Vanden Dries log.

A rare mineral formation Rutherfordin could be detected only in a few localities, where so far (as of 2013) are considered to be known about 50 localities. Its type locality Lukwengule in Ulugurugebirge is the only known locality in Tanzania.

In Germany the mineral occurred among others in the pits "Sophia" at Wittichen, " God's blessing " in Schnellingen / Haslach or Alpirsbach and " Krunkelbach " in Baden- Württemberg; in the pit " John Shaft" at Wölsendorf in Bavaria; in the uranium deposit Ellweiler in Rhineland -Palatinate and at Schneeberg in Saxony's Erzgebirge.

The only known locality in Austria is the evil Kogel at Waldstein ( Wolfsberg ) in Carinthia, where the mineral was discovered in a rock sample during tunnel construction for the South motorway A2.

Other localities lie including Australia, Brazil, China, the Democratic Republic of Congo ( Zaire ), France, Canada, Norway, the Czech Republic, the United Kingdom ( UK) and the United States of America (USA).

Rutherfordin (yellowish brown deposit) on uraninite from the Ulugurugebirge, Tanzania ( 0.9 cm × 0.8 cm × 0.7 cm)

Schoepit - pseudomorphs after Rutherfordin from the Musonoi Mine, Katanga, Democratic Republic of the Congo ( total size: 3.5 cm × 3.1 cm × 2.5 cm)

Crystal structure

Rutherfordin crystallizes in the orthorhombic space group Imm2 ( Raumgruppen-Nr. 44) with the lattice parameters a = 4.84 Å; b = 9.27 Å and c = 4.30 Å and two formula units per unit cell. The uranyl ion in this case has a distorted hexagonal- bipyramidal structure. In the figure alongside the uranyl oxygen atoms protrude upward and downward out of the plane. In the equatorial plane of coordinates is a carbonate anion four uranyl ions, so that these are connected to linear layers. These layers are parallel to each other in the crystal lattice, and such that the uranyl oxygen atoms coordinate the vacant coordination site of the carbonate anion, so that there is a slightly distorted trigonal bipyramidal structure for this.

Precautions

Due to the strong radioactivity Specimens of Rutherfordin should be stored in a dust - and radiation- proof containers, especially but never in living, sleeping and working areas. Similarly, inclusion in the body ( incorporation, ingestion) should be definitely prevented and the safety of direct body contact and worn when handling the mineral mask and gloves.

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