Mineral:  Rutile TiO2

Sample No.:  rutile.1

XRD Analysis:  Pure rutile. The crushed sample was given an HCl and 
HF bath to remove stain, after which microscopic examination 
indicated a pure sample.  (However, the transmittance spectrum does 
show weak absorption by quartz near 9.5 micrometers.  This slight 
contamination is due to abrasion of the agate mortar by the hard 
rutile during grinding for the pellet; the sintered sapphire mortar 
used to grind samples to different particle size ranges is too porous 
for use in final fine grinding for a pellet.)

Chemistry:  Ten microprobe analyses indicate homogeneity with 
respect to titanium.  The sum, however, is low, most likely due to the 
presence of niobium and tantalum (common constituents of rutile), 
which were not analyzed.  In addition, OH is present, which is also 
common, despite the nominal mineral chemistry, and accounts for 
the unusual hydroxyl band at 3.05 micrometers.

SiO2	0.09
FeO	0.38
MgO	0.02
CaO	0.04
K2O	0.02
Na2O	0.02
TiO2	95.54
	_____
Total	96.11
