Plagioclase Feldspars. 



581 



Table II (continued). 



Date 

 1912 



Initial 

 Condition 



Temp. Temp, 

 microvolts degrees 



Time 



Result 



1912 

 Dec. 

 Dec. 



Dec, 



Dec. 



19 Cryst. 14100 



24 Cry st. 1st 



preparation 14200 

 24 Part cryst. 



3d preparation 14200 

 24 Diopside 14200 



AboAn 



1386 

 1394 



1 hr. Glass with a few crystals. 

 1 hr. Glass and crystal specks. 



1913 

 Jan. 

 Jan. 



Jan. 

 Jan. 

 Jan. 

 Jan. 

 Jan. 

 Jan. 



9 



9 



9 



10 



10 



10 



1912 

 Dec. 



Dec. 



Dec. 



17 

 17 

 17 



1913 

 Jan. 

 Jan. 

 Jan. 

 Jan. 



1394 

 1394 c 



1 hr. Glass and crystal specks. 

 1 hr. Glass only. 



Liquidus 1394° ± 2° 



Ab 3 An, 



Cryst. with 

 trace o-lass 



Cryst. 

 Glass 

 Cryst. 

 Cryst. 



Cryst, 

 Cryst. 



11690 1182 

 11550 1169 



Solidus* 11 



1 hr. Slight increase of glass. 

 1 hr. No change apparent. 



<0 ± 



13680 

 13680 

 13720 

 13770 

 13820 

 13840 



Crystallized 13500 



for one 

 week, only 13410 



partly 

 crystalline. 13530 



1349 

 1349 

 1352 

 1356 

 1360 

 1363 



Liquidus 1362° 



Ab 4 Anj 



1332 



1325 



1335 



1 hr. Glass and a few crystals. 

 1 hr. Glass and a few crystals. 

 1 hr. Glass and rare crystals. 

 1 hr. Glass and very rare crystals. 

 1 hr. Glass and very rare crystals. 

 1 hr.' All glass. 



1 ± 2° 



1 hr. Glass and extremely rare 



crystals. 

 1 hr. Glass and a few crystals. 



1 hr. All glass. 

 Liquidus 1334° ± 2°, solidus indeterminate. 

 Ab 8 An! 



Partly cryst. 12580 

 Partly cryst. 12600 

 Partly cryst. 12680 

 Partly cryst. 12740 



Liquidus 126o c 



1255 

 1257 

 1263 

 1268 



1 hr. Glass and a few crystals. 

 1 hr. Glass and a few crystals. 

 Hhr. Glass and rare crystals. 

 ^ hr. Glass only. 



solidus indeterminate. 



Amelia County albite, Ab 9 sAn 2 

 Jan. 14 Cryst. coarse 



grains 10760 1102 1 hr. No change. 



Jan. 14 Cryst. coarse 



grains 11000 1122 1 hr. A very little glass. 



Accuracy not quite as great as others on account of trace of glass in original. 



