Abelsonite
- IMA 1975-013
- Nickel porphyrin
Abelsonit, also known as nickel porphyrin, is a very rare mineral used the mineral class of organic compounds. It crystallizes in the triclinic crystal system with the chemical formula NiC31H34N4 and forms up to a centimeter wide flat aggregates of pale pink, purple or reddish brown color.
Etymology and history
The mineral was found in 1969 by Lawrence C. Trudell in the type locality, the Wosco - hole in the Green River Formation in Utah. The mineral was Philip Hauge Abelson after, the President of the Carnegie Institution in Washington, DC named.
Classification
In the now outdated but still in use 8th edition of the mineral classification by Strunz the Abelsonit " salts of organic acids " belonged to the Department of where he along with Calclacit, Dashkovait, Earlandit, Formicait, Hoganit, Julienit, Kafehydrocyanit, mellit and Paceit the unnamed IX/A.02 group was formed.
The 9th edition valid since 2001 and of the International Mineralogical Association (IMA ) used the Strunz'schen Mineral classification assigns the Abelsonit in the department " Various organic minerals " and there in the unnamed subdivision " 10.CA. ", where he as single member of the unnamed group forms 10.CA.20.
The mainly common in English-speaking classification of minerals according to Dana assigns the Abelsonit into the category of " organic minerals " and then in the same department. Here he can be found as the only member of the unnamed group 50.04.09 within the subdivision " salts of organic acids with various formulas ".
Education and Locations
Abelsonit forms as a secondary mineral at surfaces of oil shale. It was created by conversion of chlorophyll and is the only known, naturally occurring crystalline porphyrin derivative. For this reason is referred to as a Abelsonit chemotherapeutic fossil. It is associated with albite, orthoclase, pyrite, quartz, mica, dolomite and analcime.
In addition to the type locality Abelsonit has yet been found in other localities in the Green River Formation and in the Piceance Creek Basin in the U.S. state of Colorado.
Crystal structure
Crystallizes in the triclinic crystal system Abelsonit in the space group P1 with the lattice parameters a = 8.508 Å, b = 11.185 Å and c = 7.299 Å; α = 90 ° 51 ', β = 114 ° 08' and γ = 79 ° 59 ' and one formula unit per unit cell.
Chemically, it is a porphyrin derivative, a total of five methyl and two ethyl owns the porphyrin ring.