750 THOMAS LEONARD WATSON 
ANALYSES OF FELDSPAR FROM SOUTH CAROLINA PEGMATITES* 
I IT III IV 
SLO Beaten 60.79 62.26 65.60 67.30 
IA One ng Hb a 22.57, 20.41 19.45 18.21 
Bes@aeetrtee 0.18 0.31 0.71 ©.79 
Mig @ eli rrins. 0.23 0.978 Oni o.14 
CaO i yaa 0.24 0.19 0.18 0.14 
INE OF ao caoor D2 I.4I 2.02 2.41 
Ke Ou eres imEccone TOR 70 II.34 Testa: 
Wem vecaasont. I.9o 1.54 0.63 0.06 
AUD) seen ete eas | meen a Trace Trace Trace 
Pi Oetiecanee: 0.09 : 
SO3.. Trace Trace 
99-73 99.61 100.19 100.19 
* Earle Sloan, South Carolina Geological Survey, 1908, Series IV, Bull. No. 2, pp. 142-40. 
I. Feldspar from pegmatite dike 8.5 miles southeast of Greenville, Greenville 
‘County, S. C. 
II. Feldspar from pegmatite dike 12.5 miles northwest of Walhalla, Oconee 
County, S. C. 
III. Feldspar from pegmatite dike 3.7 miles N. 70° W. of Pickens, Pickens 
County,.S. C. : 
IV. Feldspar from pegmatite dike 6 miles N. 55° W. of Central, Oconee County, 
Sa. 
Several varieties of pegmatite were distinguished by Graton! in the 
tin belt of the King’s Mountain area, the four most common of which, 
in the probable order of their formation, are: (1) Pegmatite, usually 
of light color and not very coarse grained, composed of microcline, 
quartz, oligoclase, orthoclase, muscovite, with in places numerous 
small red garnets and ilmenite. Crushing is apparent in much of the 
rock. (2) Pegmatite of light color, somewhat foliated, with feldspar 
as the chief constituent. The feldspar consists of orthoclase, inter- 
grown with albite, and separate small individual grains of albite, 
quartz, and biotite, with associated small prisms of monazite, and 
in many places flakes of primary graphite. These are sometimes 
worked in the western part of Cherokee County for monazite. (3) Peg- 
matite of very light color and fairly coarse grained, with quartz and 
feldspar as the only constituents in most places, but muscovite and 
cassiterite become essential constituents locally. Microcline is 
abundant, penetrated by grains of albite and slender tongues of 
1L. C. Graton, Bull. No. 293, U. S. Geological Survey, 1906, pp. 20-23. 
