Mindat Logo
bannerbannerbannerbanner
Welcome!

Lileyite = IMA 2011-021

Posted by Uwe Kolitsch  
Lileyite = IMA 2011-021
August 28, 2011 04:59PM
    
[systematic-mineralogy.com]
[forum.amiminerals.it]

Ba2(Na,Fe,Ca)3MgTi2(Si2O7)2O2F2



Edited 1 time(s). Last edit at 08/28/2011 05:00PM by Uwe Kolitsch.
Re: Lileyite = IMA 2011-021
February 10, 2012 06:04PM
    
Now in press:
www.ingentaconnect.com/content/schweiz/ejm/pre-prints/ejm2174

Lileyite, Ba2(Na,Fe,Ca)3MgTi2(Si2O7)2O2F2, a new lamprophyllite-group mineral from the Eifel volcanic area, Germany
NIKITA V. CHUKANOV, IGOR V. PEKOV, RAMIZA K. RASTSVETAEVA, SERGEY M. AKSENOV, ALEKSANDR E. ZADOV, KONSTANTIN V. VAN, GÜNTER BLASS, WILLI SCHÜLLER and BERND ERNES

The new Mg- and F-dominant lamprophyllite-group mineral lileyite (IMA 2011-021) was found at the Löhley quarry, Üdersdorf, near Daun, Eifel Mountains, Rhineland-Palatinate (Rheinland-Pfalz), Germany, and named for the old name of the type locality, Liley. Associated minerals are nepheline, leucite, augite, magnetite, fluorapatite, perovskite, götzenite. Lileyite is brown, translucent; streak is white. It forms platy crystals up to 0.1 × 0.3 × 0.5 mm in size and their clusters up to 1 mm across on the walls of cavities in an alkaline basalt. Lileyite is brittle, with Mohs hardness of 3–4 and perfect cleavage on (001). Dcalc is 3.776 g/cm3. The new mineral is biaxial (+), α = 1.718(5), β = 1.735(5), γ = 1.755(5), 2V (meas.) = 75(15)°, 2V (calc.) = 86°. The IR spectrum is given. The chemical composition is (EDS-mode electron microprobe, mean of 5 analyses, wt%): SiO2 28.05, BaO 26.39, TiO2 18.53, Na2O 6.75, MgO 4.58, FeO 4.48, CaO 2.30, SrO 2.23, MnO 1.44, K2O 1.41, Nb2O5 0.95, F 3.88, -O=F2 -1.63; total 99.36. The empirical formula based on 18 anions is: Ba1.50Sr0.19K0.26Na1.89Ca0.36Mn0.18Mg0.99Fe0.54Ti2.01Nb0.06Si4.06O16.23F1.77. The simplified formula is: Ba2(Na,Fe,Ca)3MgTi2(Si2O7)2O2F2. The crystal structure was solved using single-crystal X-ray diffraction data (R = 0.024). Lileyite is monoclinic, space group C2/m, a = 19.905(1), b = 7.098(1), c = 5.405(1) Å, β = 96.349(5)°,V = 758.93(6) Å3, Z = 2. The strongest lines of the powder diffraction pattern [d, Å (I, %) (hkl)] are: 3.749 (45) (31–1), 3.464 (76) (510, 311, 401), 3.045 (37) (51–1), 2.792 (100) (221, 511), 2.672 (54) (002, 601, 20-2), 2.624 (43) (710, 42–1). Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia, registration number 4106/1.
Author:

Your Email:


Subject:


Attachments:
  • Valid attachments: jpg, gif, png, pdf
  • No file can be larger than 1000 KB
  • 3 more file(s) can be attached to this message

Spam prevention:
Please, enter the code that you see below in the input field. This is for blocking bots that try to post this form automatically. If the code is hard to read, then just try to guess it right. If you enter the wrong code, a new image is created and you get another chance to enter it right.
CAPTCHA
Message:
Mineral and/or Locality  
Search Google  
Copyright © Jolyon Ralph and Ida Chau 1993-2014. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them. Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of thousands of members and supporters. Mindat does not offer minerals for sale. If you would like to add information to improve the quality of our database, then click here to register.
Current server date and time: September 3, 2014 02:10:53
Mineral and Locality Search
Mineral:
and/or Locality:
Options
Fade toolbar when not in focusFix toolbar to bottom of page
Hide Social Media Links
Slideshow frame delay seconds