Composition:

Petrographic Description:  An allotriomorphic rock composed of 40% pale
greenish pyroxene, 30% nepheline anhedra, 22% pleochroic brown biotite, 
7% brown amphibole and less than 1% each of opaque anhedra and apatite 
euhedra.  In addition, there was minor sphene and one large grain of feldspar 
observed in thin section.  The biotite and amphibole tended to be intimately
associated.  A brownish clay (?) mineral has formed as an alteration product
of the feldspar.  Some of the pyroxenes showed twinning along 100.  No
carbonate was seen in thin section, but spectral features area 4.0 and 5.6 
micrometers indicate its presence in small amount.

Microprobe Analysis:  The microprobe analysis revealed the pyroxene phase 
to be augite, with a rather homogeneous composition high in both soda (1%) 
and titania (1%).  The biotite composition was homogeneous, as was that of 
the amphibole, the latter approximating kaersutite in composition (high in
alkalis, approx. 2.3%, and high titania, approx. 3.9%, by weight).  An 
opaque phase analyzed was high in iron (74%) but contained silicon approx. 
3%; the balance may be made up of chromium (chromite?) but this seems 
unlikely because of the chemical nature of the rock.

Chemical Analysis:
SiO2  43.08
CaO  12.13
TiO2  2.6
NaO  3.49
Al2O3  13.1
K2O  3.39
Fe2O3  2.6
H2O  1.87
FeO  7.32
P2O5  0.54
MnO  0.20
MgO  9.66
TOTAL  100.5  (CO2 not analyzed)
